## Wednesday, June 1, 2011

### Chapter 9 Review

Alright so here's a quick review and some sample problems from chapter 9. The test is on Thursday June 2nd. There is a calculator and non calculator part so remember your green cards!

9.1 Exponential Growth

The exponential curve is different than a parabala or hyperbola. It is also an asymptote.

Some formulas associated with exponential growth are as follows:
Geometric Sequence- $a_n = a\,r^{n-1}.$
Compound Interest-
Exponential Function- y=ab^x

9.2 Exponential Decay. This is very similar to exponential growth, but it depreciates. The growth factor is between 0 and 1, so there is a decrease.

9.3 Continuous Compounding. This is tricky, so watch out on the test for the wourd CONTINUOUSLY!!!! This is differnt than y=ab^x, and it is guaranteedthat some of will goof this up on the test. The formula for this is known as Pert.
A = Pert
P is the initial condition, e is on your calculator, r is the rate and t is time.

\$7808 is invested at 11.9% and compounded continuously for 17 years.
7808e^1.0119x17= \$59036.08

9.4 Fitting Exponential Models to Data
For this your calculator is essential. In order to get into a lists and spreadsheets, hit home, 1, 4, and input date into the spreadsheet. Once your data is in hit menu, 4, 1, A, in order for it to analyze the exponential regression.
9.5 Common Logarithims

Exponential form 1o^7=10000000 Log Form log10 10000000=7
The answer is always the power, so they way to think of it is 10 to the x power equals 10000000.

9.7 Logorithims to bases other than 10

It is the same concept, think about the exponent as the answer. 3^4=81. In log form, that looks like log3 81=4. Although the base isn't 10 don't let it throw you off, it is the exact same thinking and way yo put it into log form.

9.8 natural logarithms
n is the natural logarithm of m, written n=ln m, if and only if m=e^n.
e is also the inverse of ln.

9.9 Properties of Logarithims
x^0=1
x^m x x^n= x^m+n
x^m/x^n=x^m-n
(x^m)^n=x^mn

9.10 using logarithms to solve exponential equations
In this lesson, you have to solve b^x=a. There are a couple ways to do it. Of course you can use CAS but you can use logarithms to solve the equation.

ln2=ln9e^12r)
ln2=12r
r=ln2/12
.0578

## Tuesday, May 17, 2011

### 9.5

Today in class, we learned about logarithms. We first went over how to find the "log" button on a calculator. You press CTRL 10^x. We then started on the 9.5 notes and sketched a graph of the exponential function y=10^x. From there we found the inverse by switching x and y. This is where the new function, logarithms, comes in. We found that the inverse of y=10^x is x=10^y, or the log formula. After graphing both we compared and contrasted the two equations.
y=10^x y=log x or x=10^y
Domain: all reals x>0
Range: y>0 all reals
x-int.: none (1,0)
y-int.: (0,1) none
Asymptote: x-axis y-axis

After, we did some examples without our calculators. The first problem we looked at was log 10^100. In order to figure it out, we set in up as 10^? = 100. From there it was easy to figure out that the answer was two. We then moved on to decimals. The next problem was log 10^0.1. In order to figure it out we changed it to 10^? = 1/10. We then figured out that our answer was -1.
Some more examples are:
log 10^ 1,000 = 3 log 10^ 10 = 1 log 10^ 1000000 = 6
log 10^ 5 = .669 log 10^ 30 = 1.477

It is important to notice that log 10^ (-100) does not work. This is because you can't raise 10 to a value and get a negative number. Another important thing to notice is that the base does not have to be 10. A problem can be log 9^ 81.

The next set of problems that we did were very similar to the previous examples. However, they did not included a base number. When logs do not have a base number, it can be assumed that 10 is the number. "Log x is called the common logarithm, so log 10^x is the same as log x."
Examples:
log 10000= 4 -This is because you assume the equation is written as log 10^ 10000.
log (o.oo1) = 3 log 10 = 1 log 7 = .8451 log 316 = 2.4997

We were then introduced to another set of equations. Log x = 4. It looked difficult, however, using the two methods we previously learned, it was pretty simple. First we put in 10 as the base because we learned that you can assume a log without a base is 10. Then we changed the equation around to read 10^4 = ?. This equation resembled the ones we had done previously. We then used our green cards and found that x = 10,000.

The last lesson of the day was the conceptual question., "Between what two integers is log 7598?" To solve this we asked ourselves 10^ ? = 7598. We then plugged in number for 10^ ? and found minimum and maximum values of 3 and 4. These two numbers worked because 10^ 3 = 1,000 and 10^ 4 = 10,000. We knew that 3 and 4 were the two integers because 7598 fit in the middle of them.
Examples:

log 172: log .4:

10^ ? = 172 10^ ? = .4

10^ 2 = 100 10^ 0 = 1
10^ 3 = 1,000 10^ -1 = .1

Answer is 2 and 3 because 172 fits in Answer is 0 and -1 because .4 fits in
between 10^2 and 10^3. between 10^0 and 10^-1.

If you still need help the 9.5 notes are located on moodle. Also the homework for tonight is 905 - 1, 3-11, 14-16, 18, 21-23.

## Wednesday, May 11, 2011

### Chap 9 Section 3: Continuous Compounding

Hello class. At the beginning of the day, Mr. Cope gave a 5 minute review on sections 9.1 and 9.2. He simply taught exponential growth (9.1) and exponential decay (9.2). He taught the equation y=ab^x. A being the number you begin with, b being the growth factor (growth b>1, decay 0<b<1) and the x being the number of years being used. This was just a quick review of what was taught on Monday and Tuesday.

Next Mr. Cope handed back the tests and homework quizzes we took last week. Unfortunately, Teacher Logic no longer shows the class average so there will be no comparison to period 1 in this blog post. Anyway, we were able to compare our answers to Mr. Copes key and then we moved on to today's lesson.

Today we learned about continuous compounding. We began with a chart showing a bank pays 100% interest for 1 year. So we went through annually, quarterly, monthly, daily, and hourly using the equation P(1+r/n)^nt. The final value (hourly) was very close to e (2.71828) or Euters number which is used to represent exponential growth. So the formal equation for Continuously Compounded Interest is a=Pe^rt. P stands for the original number, e stands for Euters number, r stands for either the growth of decay (growth=if number is positive, decay if number is negative), and t stands for the number of years. We then did an example 1 which was "Suppose \$1800 is invested at an annual interest rate of 7% compounded continuously and the money is what happens in 5 years. So the equation would be 1800e^.07(5). You then would solve it on the calculator and your answer should be 2554.32.

Moodle notes: http://gbs-moodle.glenbrook225.org/moodle/mod/resource/view.php?id=13797

## Friday, May 6, 2011

### Woah!!!!!!

So I saw this pic whilst browsing the internet and I was like, BAM! MR. COPE!

## Wednesday, April 20, 2011

### Multiplying Polynomials

Hello class unfortunately I forgot to this blog the night i was assigned to but here is what we learned in section 2 of chapter 11.
We first started out by classifying polynomials by the number or terms
• Monomial- polynomial with one term (ex. 10 or 14x)
• Binomial- polynomial with two terms (ex. x+2 or 4x^4-7x)
• Trinomial- polynomial with three terms (ex. x+2+3x^2)
After getting a little off task with the usual 10-15 minute discussion we began examples on the back page of the notes.
(-y+6)(y^4+2y^2-3) first you must foil it by hand which we learned in some older chapters. when you foil that you get -y^6-2y^4+3y^2+6y^4+12y^2-18... then after you reduce that all down you end with -y^6+4y^4+15y^2-18.
But if you would rather not go through all that fun you can simply type it in to your calculator and get the answer fully reduced and without straining yourself in the slightest.
Hello class, yesterday we learned about factoring. There are 3 special cases of factoring
• Greatest common factor
• Difference of Perfect Squares
• Perfect Square Trinomials
Heres an example of a problem in which we need to solve using the Greatest Common Factor

5wz+25w^2(z)-35w^3(z)

First we need to find the GCF. All of the numbers are multiples of 5 so 5 would be a GCF so it would come outside the parentheses.
5(__________)
We can also see that every one of them has at least one w in it so that would also come outside the parentheses.
5w(_________)
We can also see that there is a z in every number so that too would come out of the parentheses and now you divide everything inside the parentheses by 5wz and your product should look like this
5wz(1+5w-7w^2)

Now heres an example problem with Difference of Powers Squared
x^2-1oo
the form for solving this kind of problem is a^2-b^2=(a+b)(a-b)
so we need to think. what times what equals x^2? well that would just be x
(x+__)(x-__)
Now what times what equals 100? well that would just be 10.
(x+10)(x-10)
and do not worry about the 10x and -10x because they cancel each other out.

And here is an example of a problem with perfect Square Trinomials. They are called that because the first and last numbers are perfect squares.
9x^2+6x+1
Now what times what equals 9x^2? 3x so,
(3x)(3x)
Now what times what equals 1? 1 so,
(3x+1)(3x+1)
and that is ok because when you distribute it 3x plus 3x equals 6x
Now we all know that something times itself is just that something squared so the final answer would look like this,
(3x+1)^2
I hope this blog is useful in understanding this concept. Thanks.
-Tim Kirby

## Thursday, April 14, 2011

### 10.4 (Day 2)

the angle created by a radius along the circumference of a circle.

Conversions

To convert from radians to degrees: multiply by 180/ㅠ

To convert from degrees to radians: multiply by ㅠ/180

For example,

11ㅠ/ 7

It's radian, so you multiply 180/ㅠ = 282.9 degrees

If you convert degrees to radians, then you leave ㅠ(pie) in answer

I can't put any images on here, because it doesn't work for me.

But, if you want to see completed Unit circle, go to

Based on 30-60-80 traingle and 45-45-90 tirangle,

you can find out the cosine and the sine of angle of unit circle.

For example,

30' has cosine of square root 3 over 2

You can get this by knowing 30-60-90 triangle

SO! it is squre root 3 over 2.

sine of 30' is 1/2.

sine is opp/hyp

So! it is 1/2

It's same way with 45-45-90 triangle.

ALSO

In Unit circle,

1 & 2 quadrants is sine POSITIVE.

2& 3 quadrants is cosine NEGATIVE.

you have to becareful of this

-Michelle S.

## Wednesday, April 6, 2011

### 10.4

1o.4 ( the unit circle definition of Cosine and Sine)

Today we learned about the unit circle. (shown above)

We continued to explore Trig and the uses of Sin and Cos.

MAIN POINT

X coordinate- Cos

Y coordinate- Sin

the positive degrees on the unit circle goes counter clockwise starting in the right

(x on the picture above)

they go 0-90-180-270-360

opposite if you are moving in the negative direction

check out the notes for a better explination..

Remember the homework was changed to just the top problems on the assignment sheet ( 1,4-7,13,15-17, 21) because we did not finish the lesson and there is a quiz tomorrow :)

-cathrynR

### April 5, 2011 Period 2 Adv. Algebra, Lesson 10.2

Hello period 2 Advanced Algebra, I'm here to talk about lesson 10.2 that went down in class on April 5. 10.2 (More Right Triangle Trigonometry) was a lesson composed of Inverse Trig Functions, and how to find the measure of a given angle using the inverse of a trig function.

Trig Functions
Cos
Sin
Tan

Inverse Trig Functions
Sin^-1
Cos^-1
Tan^-1

We use the inverse trig functions to solve for an angle.

I.E. if two sides to a right triangle are 9,14. Then you can find the measure of the other two angles by using the inverse of cosine for one angle and the inverse of sine for the other angle.
For angle A, you would plug into the calculator, Cos^1(9/14) and the outcome would be 50. That is your angle measure. You would continue this with the inverse of sine for angle B.

If you are given a right triangle and two sides you can find the rest of the angles using inverse trig functions.

For more information from class just go to moodle and go to Ch. 10 notes and click on 10.2 and you're there.
-Mike s.

## Monday, April 4, 2011

### bonjour, maintenent, je n'ai pas les chats dans mes pantalons

Howdy-Doo, all. It’s time for some refreshingly correctly punctuated and spelled math commentary, thanks in part to my lovely pal spellcheck. (I spelled the words punctuated, commentary and refreshingly all wrongly just now.)

Anyways…the lesson of 10.1 was presumably an almost a review-type lesson, it being the first of the unit and all. What is this unit that we have begun, one might inquire…. Well Trigonometry of course!

Trigonometry being of course the study of triangles and such, a review of what little trig we have as of yet learned in our geometry course was in order.

Alright, so right triangles are really kind of cool little things in that they have many inherent similarities simply do to the fact that they are constricted in a way so that all of their ratios end up having to be constant despite a change in the size and/or shape of the triangle.

The three special ratios that we have learned to utilize are as such:

SINE

The sine ratio describes ratio between the opposite side to the specific angle and the Hypotenuse of the triangle

COSINE

The Cosine ratio describes the ratio ‘tween the adjacent side to the specific angle and the Hypotenuse of the triangle

TANGENT

The tangential ratio naturally occurring in any given right triangle describes the ratio betwixt the opposite side to the specific angle and the adjacent side to the specific angle

So I am just going to assume that y’all are familiar with the parts of a right triangle, hopefully we all remembered at least this from Gemetry.

Now there are a few more really cool interesting things about right triangles that we learned about today:

For instance, the SIN of any angle will have the equivalent value to the COSIN of said angle’s compliment

Now the next thing that we learned, and this was probably the meat of the lesson, was that you can use these ratios to find missing side lengths in right triangles.

Let me walk you through this example to find the length of the hypotenuse and the last side:

Okay so first we need to decide what ratio we can use to easily find the length of CB

I chose TAN from the 30 angle simply because I like my variable on top of a fraction

So: TAN(30)=

Then multiply by 15

So: 15TAN(30)=x

Then use the calculator to simplfiy and you get: 2.66=x

Thar you go, you all can now solve right triangles using their ratios, Yay!

Have a nice night everybody, I hope nobody is up too late.

## Sunday, April 3, 2011

### Chapter Eight Review!

On March twenty-third, we reviewed for the upcoming chapter eight test. The previous night's homework was 8.8, so first in class we reviewed that. 8.8 wasn't too hard, but I had some questions about number twelve and number fourteen was on a homework quiz. Next we worked on a worksheet to help us review. Some of the main concepts were simplifying fractions such as number six on the worksheet (for some reason my computer isn't letting me copy/paste from the symbol website >:( )How to do this is to take the complex conjugate of the denominator and multiply both parts of the fraction by it, foil, and solve from there. Another key idea is simplifying multiple-variable nth roots. (such as numbers 15-20 on the worksheet) This is done using the "Jailbreak" method (reference section 8.5). Another concept is solving for all real solutions (numbers 7-11) this isn't too hard, we've been solving for a variable since pre-algebra, but note that for example if you had the fourth root of x that equals ten, you would multiply each to the fourth power and solve from there. Also watch negatives, they might lead to undefined results. A rule to know is that a negative number will never have a real solution if it is to an even root. If it does, it will be undefined. The homework for the day was to do section 8R3, numbers 1-12 and 17-21. Happy spring break!

## Tuesday, March 22, 2011

### Math Symbols

Here is a great website for inserting math symbols into your blog posts:

Scroll to the bottom and you can create the symbol you need.  Then copy and paste into your document or blog post.  Let me know if you encounter problems.

## Monday, March 21, 2011

### 8-7

Hey Everyone, I will keep the short because I know from personal experience that I do not like to read long blogs.
Here is what we learned today:
= positive or negative (if exponent is positive then output will be positive. If exponent is negative then the output will be negative)

= Undefined (no matter what your calculator says, and it will say many things….)

= Imaginary.

= Negative

= Undefined

Have Fun doing the homework. I know I will.

## Thursday, March 17, 2011

### Review for ch8 quiz

Today we went over the homework, assignment 8.6, pretty solid assignment not to bad. But reviewing the homework was different because we used the reverse color thing on the elmo! Then we got a review that we went over quickly, just the pointers from each section that we should know for tomorrow. We had the rest of the class to do the review worksheet, the usual work with a partner/ listen to your ipod. So basically just the typical review day.

Some quick reminders for tomorrow's quiz:
- when u have a square root in the denominator of a fraction you want to move it to the top. So multiply the square root on the bottom to each numerator and denominator of the fraction. Also remember that simplifying first may be easier than doing at the end.

-If you are having trouble with the cube root or the forth root stuff remember to just write it out then group them.

-Don't forget the geometric mean! Multiply each number then depending on how many numbers there are in the set use that number root then the number all the numbers multiplied up to.

If you have any more questions you could:
-email Mr. cope ( bcope@glenbrook225.org)
-review the note key on moodle (http://GBS-Moodle.glenbrook225.org/moodle/course/view.php?id=1304)
-get the answers from review sheet (http://gbs-moodle.glenbrook225.org/moodle/file.php/1304/8.4-8.6_Review_Key.pdf)

Hope this helped! Good luck tomorrow and Happy St. Patty's day :)

## Tuesday, March 15, 2011

### March 15, 2011 Lesson 8.5

Homework: Assignment 805

Today we skipped homework checking and went straight to the lesson, so it's probably best to use Mr. Cope's moodle key to check your homework before the homework quiz, whenever it may be.
We then began to simplify radicals to tie together past lessons with yesterday's lesson, all to today's lesson. Mr. Copes goal: for us to be able to simplify ⁵√64x¹¹y²⁷z⁵³ to 2x²y⁵z¹⁰ ⁵√2xy²z³ .

Mr. Cope skipped the formal definitions, for a more practical approach, by using one of his colleagues explanations of factoring, The Jailbreak Method. To use the Jailbreak method one needs a pair of the same number to "break out" of the radical, while the unpaired numbers remain under the radical.

He then linked this to todays lesson by explaining that when you factor out various types of radicals like ∛ ∜, instead of just looking for a pair, you look for the number thats written. In these cases, groups of 3's or 4's.
To simplify radicals, you must factor out the radicals, then look for the groups, indicated by the number before the radical. The number(s) that can complete the number needed "break out" of the radical, while the rest must remain under.

Ex: ∛80
/ \
2 40
/ \
2 20
/ \
2 10
/ \
2 5
While the purple 2's form a group of three, the red 2 & 5 don't, the the answer would then be:
210

To multiply radicals you need like terms, i.e. ∛2∗∛6 then you multiply, and simplify if necessary. In this case:
∛2 ∗ ∛6
∛12

another example from the notes is:
∜3⁶w⁷ ∗ ∜3²w²
∜3⁸w⁹
3∗3∗w∗w∗∜w
9w²∜w

***Note*** to simplify radicals with variable, if it helps you can
write them out, and box the groups of variables.
Ex: ∜16n¹²
/ \ nnnn nnnn nnnn
2 8
/ \
2 4
/ \
2 2
The answer is 2n³ because the 2's form a group of 4, and the there are 3 groups of n's able to be formed.

Hope this helps, if not you can always look back to the moodle notes or ask Mr. Cope for help.

## Monday, March 14, 2011

Today we got the results back from our 8.1-8.3 quiz. Overall, the class did pretty well; the average was and 80%. We went over a few problems but there was little confusion so we moved on.

Next, since we didn't have any homework, we skipped right to the lesson, 8.4. To begin lesson 8.4, Radical Notation for nth Roots, we reviewed some of the ideas from previous sections that are critical in understanding this one. The two most important are probably: an

x1/2 = √x

n√xm = xm/n

A useful example (from the notes) is:

Suppose x ≥ 0. Simplify 3√x12.

What you should do is take (x12) and raise it to the 1/3 power.

(x12)1/3 = x4

In lesson 8.4, however, it gets a little more complex. I hope I can help you understand it. Instead of being formatted like the example above, problems in this section look a little more like this:

Suppose x ≥ 0. Rewrite √(√(√x))). It’s pretty tough to write that on word, but it’s basically the square root, of the square root, of the square root of x. You would write it using radical exponents, like so:

((x½) ½) ½ or, since you multiply ½ by ½ by ½, its x1/8.

So, if you suppose x ≥ 0, can you solve 6√y4 ?

Here is how you would: (y4)1/6 = y4/6 = y2/3

The homework for tomorrow is As. 804. I hope this was helpful! If you have any questions, the notes are on moodle: http://gbs-moodle.glenbrook225.org/moodle/login/index.php

-Meg Karnig

## Sunday, March 13, 2011

### 8.1-8.3 Quiz

Hello clase,
I will summarize the extent of our days activities on Friday the 11th.
We took a quiz.

Ok, so the quiz was on sections 1-3 of chapter 8. As for how the quiz went, i thought that i did good, and i thought that i knew the material really well, though as i recently found out, i didn't seem to do very well on it...

You will remember that on this quiz we were not allowed to use our beloved ti inspire calculators, and instead we were forced to use the old school calculators that Mr. Cope said he used in High school, which then put him in a solemn state of mind, in which perhaps he pondered for a minute, flowing through wonderful memories of his high school career. He then made it clear to us that real life was much better, and we became confused because we assumed that we were in real life. I think we all left class that day shaken...

Anyway, as for the quiz material, you could obviously read all the posts below which go into far greater detail about each section, though ill give you an overview of all three sections.

Pause: I just realized i forgot my math folder somewhere.. or i lost it. So give me a couple seconds to look up the notes on moodle, which you can get to by going to http://gbs-moodle.glenbrook225.org/moodle/. What a great example of what you can find on moodle. You should view me as an example of a common mishap that you can learn from.
Perhaps you forgot your folder, and you have algebra homework due the next day...
WHOA
Ok, once you've recovered from the shock, you may proceed to http://gbs-moodle.glenbrook225.org/moodle/
where you can find not only every notes sheet from every section so far, but also the answers to the homework from the previous night. Not only that but you can even access the online book, with a code and a link that is posted on the algebra moodle page.
So as another example, Say you did your homework, and in class you checked each one of them with the answers Mr. Cope puts on the board. When you get home you realize: i accidentally forgot to correct one of the questions on my homework.
OK, OK
You now wont be freaking out, because of this vital information i have just given you. Instead you will immediately remember the Wisdom of Téo. Go to moodle. here is the link once again:
Also the link to go to the book is http://www.ucsmpmath.com/
and the access code for the book is: 1CED23F3

So now that i found that excellent connection in which to point you to moodle for all your needs and desires, let me get back to explaining the quiz material.

8.1
-Composition of functions
if you remember, this is when we simply put one function inside of another. From previous lessons we have learned that when we see f(x) notation, whatever is in ( ) gets plugged in place of x. This same concept applies here. though instead of placing a simple value such as 5 inside the parentheses, we insert a whole other function. Sometimes, if theres variables we insert the entire other function into the ( ) though for some we simply simplify one function and insert its value into the other, which we then solve.

example:
theres no good way of showing this here but...

If we define 2 functions, g(x)=x^2 and f(x)=3/4X-10
and we want to evaluate f(g(2))
we know to solve g(2) first because it is the furthest to the right, and like Mr. Cope analogied to us the other day, its like reading Arabic.
So we would first solve g(2)
g(2)=2^2=4. We plug in 2 to the function g and we get 4.
Next we insert the 4 into the function f, because as you can see f(g(2)), we plug in the result of g(2) into f.
f(4)=3/4(4)-10=-7. We get -7 when we plug in the result of g into f. So -7 is the answer.

I hope that you can somewhat understand what im saying here.

8.2
-Inverses of Relations
there are three rules for inverses.
1) a rule for g can be found by switching x + y and solving for y
What this means is that if we have the equation y=2X+5, then we simply make the y an x, and we make the x a y, like so..
X=2Y+5
2) A graph of g is found by reflecting f over the line y=x
this may sound confusing, as i didn't exactly understand it myself at first, but no matter what, the inverse is reflected literally over the equation y=x. Simple as that
3)the domain of g is the range of f. the range of g is the domain of f
This is pretty straightforward, though ill explain it anyway. the domain of g is the range of f and the range of g is the domain of f. ok theres no other way to say it. um...

8.3
-Properties of Inverse Functions
The term thing used to reference the inverse of a function is f^-1
For points on a graph, the inverse of a point is found by switching x and y, much like in 8.2 above. So for the point (a,b), the inverse is (b,a).

We learned in this section how to determine whether or not the inverse of a function is a function, by applying the horizontal line test. Its just like the vertical line test but horizontal.

The above image, assuming it shows up, illustrates how to use the horizontal line test. We know from this graph that the inverse is not a function because each horizontal line intersects the graph at 2 places.

This image now illustrates when the horizontal line test would pass. Here, each horizontal line intersects the graph at only one point, which tells us that the inverse is a function.

Now once again, this is acting simply as a broad summary of all the sections that were on the quiz but if you would like to see the more in depth ones for each section, you can find them below this post. Also ill post the link to each:
8.1: I could not find for some reason, the 8.1 blog post on the period 2 site so ill post the link to the one that i found on the period 1 site, which should be better anyway since period 1 is so much better than us haha, just kidding. http://advalg1011p1.blogspot.com/2011/03/chapter-81.html

If you made it this far to read this, thank you and i hope that i was able to somewhat give you an overview of our day and our quiz on Friday.

## Thursday, March 10, 2011

### 8.1-8.3 QUIZ TOMORROW

We started today's class by checking our homework. We made sure that we understood all of the questions and got all the right answers. Then Mr.Cope handed out a review packet for quiz 8.1-8.3 quiz. The quiz is tomorrow. REMEMBER WE ARE NOT ABLE TO USE OUR CAS CALCUL ATOR ON THE QUIZ!!

Here are some resources:
-You can look on Moodle for
2. Chapter 8 notes
3. 8.1-8.3 review key
4. You are also able to access the online textbook

-In the textbook
1.Page 516- Page 536 is lesson 8.1-8.3
2.Page 574- Page 577 is the review section.

Sorry...This is not one of my best sections. I'm still reviewing. Next post will be better!!

### Remember non CAS Calculator

Remember to bring a non-CAS calculator to class tomorrow for our quiz.  A TI-83 or 84 is fine or a simple 4-function calculator.  I am available before school if you need help with the concepts.

## Wednesday, March 9, 2011

### 8-3 Properties of Inverse Functions

At the start of class we of course reviewed the previous day's homework, which was section 8.2. After our homework review we wet over Mikaela's last post on section 8.2. This took up a good chunk of time. Mr. Cope also talked about how he takes things personally when he doesnt need to. Like when a student falls asleep in his class, it's not his fault. The student definetly should have went to sleep earlier and possibly slept in the previous class so that it didn't happen in Mr. Cope's. We then talked about how Mr. Cope and how he hasn't caught anyone texting during class in a while.

Section 8.3 is about the properties of inverse functions. Here's the basic objective you need to know before you start computing anything:

1. We denote the inverse of a function as f^-1. (f^-1 means the inverse of a function)
2. For every point (a,b) on the graph of f, the point (b,a) is on the inverse graph. (the point (a,b)'s inverse is (b,a))
3. To determine whether the inverse is a function or not without graphing, we apply the horizontal line test. (use the h.l.t. to see if the inverse will be a function without graphing)

Given the general equations y=x, y=x^2, and y=x^3, we know that y=x is a function using h.l.t., y=x^2 is not a function because it doesn't pass h.l.t., and y=x^3 is a function because it passes h.l.t.

The three steps to finding an inverse are...
1. Replacing f(x) with y
2. Switching x and y
3. Solve for y

When combining any two functions the inverse "undo" eachother. For example when we plugged g(f(x)) and f(g(x)) into the calculator both outcomes equaled x.

On a test Mr. Cope may say are these two functions inverses? To solve this you would simply plug the functions into eachother [g(f(x)) and f(g(x))].

The inverse function theorem states that two functions if and only if f(g(x))=x and g(f(x))=x.

The tricky part was power functionsand inverses.
f(x)=x^6's inverse wouldn't be a function because it's a parabola. Parabolas never ever pass h.l.t. It causes a problem when you attempt to plug negative numbers into the inverse function. X can't be negative in an inverse. So to take care of that you can restrict the domain to X is greater than or equal to 0.
f(x)=x^an odd number passes h.l.t., and is much simpler than an even power function.

Next blogger is... Emma B!

## Tuesday, March 8, 2011

A couple days ago we took the chapter 7 test. This test consisted of two parts: a no calc. section but we were able to use our "green cards" and then a calculator section.

In preparation for this test we had a review sheet the day before. This review sheet first discussed what would be on the no calc. part: it went over power functions, geometric sequences with recursive,explicit formula and domain and range. Also on the review sheet Mr. Cope gave us practice problems that required us to use properties of powers with negative and fractional exponents. On the back of the sheet it discussed the calculator part of the test: topics it covered were compound interest,word problems, and using properties of powers with numbers not on the "green card".
If you had trouble with any of these topics or problems remember you can always refer to moodle or your notes from class.

Something I recommend when we are reviewing before the test that you(Mr.cope) actually discuss and go over it with us in class rather than us just doing it ourselves and making us go on moodle if we want to check our answers because im a sure most of us forget and just wing it on the test not even knowing if we did the problems correctly.

And as far as the test goes I don't think there should be a no calc. part because the majority of the quiz's you gave us for this chapter were no calc. and us as students tend to not do as well on them, therefore bringing down our scores. but overall the test was ok, I just wish I had more review and better assistance from the teacher.

mikaela allmon

### Tuesday, March 8th, 2011 Lesson 8.2

Today in class we went over the homework we had over the weekend which was 801, then viewed the blog. Mr. Cope gave us the rubric on how we would be graded for the blog posts, then started the lesson.
Lesson 8.2: Inverses of Relations
3 Important things to know about inverses of relations:

Suppose f is a relation and g is the inverse of f;

1) A rule (or equation) can be found by switching x and y (solving for y if necessary)

2) A graph for g is found by reflecting f over y=x,

3) The domain of g is the range of f, and the range of g is the domain of f

An example of inverse relation is this;
Let f = (1,4) (2,8) (3,8) (0,0) (-1,-4)

The inverse relation of this would be;
(4,1) (8,2) (8,3) (0,0) (-4,-1)

Another thing to note, is that the f is a function but the inverse of f is not.
This is because when you reverse x and y, there becomes (8,2) and (8,3) which means it is not a function.
You can also find out if the inverse is a function by seeing if it passes the horizontal line test.

The domain of f is ( 1, 2, 3, 0, -1) and the range is ( 4, 8, 0, -4)

The domain of the inverse is (4, 8, 0, -4) and the range is (1, 2, 3, 0, -1)
You should note that the domain and range swap when it is the inverse.

Another example is f 9x0 = 1/2x + 4
The work I did to find the inverse is;
I rewrote the equation to be y = 1/2x + 4
Then rewrote it as x = 1/2y + 4
Then I subtracted the 4
So its now x - 4 = 1/2y
Then I multiplied both sides by 2 to get ride of the fraction
So it would now be 2x-8 = y which is the final answer.

I hope this helps!

Homework :
802 and the 3 problems on the back of the worksheet.

The next scribe will be Leah.

## Wednesday, March 2, 2011

### March 03, 2011

It has been yet another wonderful day in Mr.Cope's second period Advanced Algebra class.
First we started our day off by getting a homework quiz, which usually either helps your grade or hurts it. Along with going over our partner quizzes, that were not so phenomenal according to Mr.Cope and the would not count for points, so hurray for those who did not so great. We then received our very structured and helpful Chapter 7 review sheet that we did in class, and Mr.Cope so kindly reminded us that we should access Moodle, that has many helpful resources, such as extra copies of our green cards that we are allowed to use for tomorrow's Chapter 7 test, and there are also review sheets and answers on Moodle for those that are interested.

Don't forget to study for our Chapter 7 test tomorrow, :)
Good luck.

## Tuesday, March 1, 2011

### 3/1/2011

Hey everyone! Today in class we went over the homework (708 A & B) and then we took a partner, open-note, no calc quiz! Also, we talked more about this blog and what we think of it. There were varying opinions on it, ranging from 'I don't think this is going to have any affect on anyone' to 'I really like that we will get to interact and almost talk to each other!'
Okay, so Victoria G is going to post the next one! :)

### Reflections from Class

I just wanted to say thank you for your honest reflections today in class about what this blogging process will be like.  I do want it to succeed, but I don't have any delusions that it will be amazing and revolutionary right away.  If it turns into something great, it will take time and effort on both of our parts.  We will need to reflect on and share what is working well and what needs to be improved.  I appreciate your patience and your willingness to give it a try.

## Monday, February 28, 2011

### 2/28/2011

Todays class was pretty easy. Throughout the class period we started to create our usernames for this blog. Mr. Cope explained how to do it in class then we walked over to the math lab to create our accounts. After setting ourselves up as authors, we were told to "grade" a practice Chapter 7 math test that Mr. Cope took. He purposely made mistakes and we had to find them and send them in an e-mail to him.

All in all, it was a fun day!

### bonjour mes amies

creo que este es un buen idea

### And yae, Mr. Cope hath spread light to a new land

Hello everyone. I think this a genuine idea that is full of potential! Mr. Cope is the cat's pajamas and the bee's knees all rolled into one!

### My First Post

This is a quality idea.

### First Post

Well you made it to our class blog...good job!  This is the place where we will, as a class, create the narrative of what goes on in our class.  We will discuss the content of the lessons, help each other clear up confusion, and reflect on the learning of mathematics.  Please remember that this is a public online space that is viewable by the entire world, including me, your parents, and your peers.  Write as if the whole world will read!

My expectation is that you will use this space to push learning outside of our 50 minutes together each day.  You and I are the authors of this blog.  Please use the comment feature below each post or make your own post to contribute to the conversation!