Tuesday, October 27, 2009

Yesterdays class was a catch up period, one of my favs. I worked on some accelerated math, and got 79%, wasn't bad, but I have to do some objectives over again which sucks. I was very happy we got a catch up block because I am somewhat behind in this class. And stressing over this math test comming up on thursday.

Tuesday, October 20, 2009

Today in class we did some more practice/considerations with identities. We learned about EXTRANEOUS roots.- "they are answers that look good on paper but practically don't make sense".
When we are doing our questions, all solutions must be checked for validity. In an equation you want to bring everything to one side, and when you have a question like cos(x)+1=sqare root thre sin(x), you always want to sqare both terms to get rid of the radical.

Monday, October 19, 2009

Today in class we learned how to simplify. Completely. And learned techniques to assist "proofing" idenities. There was eight different techniques. Such as reduce/simplify, work each side independently to some intermediate expression, DO the multiplication/subtraction of the rational expressions, Simplify GCF'S ALWAYS, FACTOR, try multiplyinf both numerators/ denominators by same expression, and lastly, if possible rewrite all trig. functions as sin(x) or cos(x); look for patterns.
And we learned to prove by LHS and RHS. I find it kind of complicating,but hopefully I will catch on.

Friday, October 16, 2009

Last class we got a CATCH UP CLASS! I especially love these days. Because I usually have a lot of catching up to do. I worked on exercise 12 that is due for monday. I unfortunatley did not finish, but I will finish it sometime this weekend.

Thursday, October 15, 2009

Last class we wrote a math test. It was on trig stuff and transformations. I am not feeling too confident at all with it, hopefully I can do a re-write because i've got a feeling that I was not even close to a pass.

Tuesday, October 13, 2009

Last class we got our homework checked. I got a 100%, no big deal or anything. So while we got called one by one down, we had to work on exercise 11.

Thursday, October 8, 2009

Last class we learned reciprocal functions. Reciprocal means fliped over. ex) a/b---->b/a. We learned that a reciprocal function is in which the numerator and denominator switch places. Then we learned how to graph it. The graph of a reciprocal function, compared to its orig. function, is curved and has one or more asymptotes along the x axis. The asymptote of the reciprocal function is found where the function crosses over the x axis. If the orig. function decreases, the reciprocal function will increase. We leanred this as: "GREATERING" and "LESSERING".

Wednesday, October 7, 2009

Last class and the class before we learned some more and more graphing, what joy! We used a table if values and what not to help us. We compared items like f(x)n to -f(x). We made a table of values and made a therefore that flip across x-axis when f(x) becomes negative f(x).
One to one functions- have inverses (passes the "horizontal line test". ex) only one point of intersection maximum with a horizontal. We then determined if the fxns are ODD, EVEN, or NEITHER.

Monday, October 5, 2009

Last class we learned all about transformations. We've learned the different graphs, and went on graphmatica and seen what they all looked like. Then moved on to translations. Def- every point in the relation moves some direction, same distance. Translations(slides)ONLY ever move the ref. function either left/right. We learned the general form: y=f(x-h)----->L/R. OR y=f(x)+k---> U/D, y=f(x-h)+k
h moves h units RIGHT. And k moves k units UP.

Friday, October 2, 2009

Yersterdays class was the test,but a few of us chose to write it a day later.This really helped me because i just looked at the practice test yesterday and today so i got alot of help. I think if I would have wrote it yesterday I wouldnt have been as prepared as I was today when I wrote it.

Graphing trig functions

So last class(three days ago) we were "tieing ends" on how to graph trig functions. Some definitions you might call them, are period- which is the smallest horizontal space within which repeats itself exactly once. A period of sin (sin curve, cosine curve) equals 2 pi/ b. Your domain is you x value, and your range is where it crosses the x axis. An exapmple question is f(x)=asin(b(x-c))+d. "a" tells us that it stands for the amplitude(which is the distance). "a" value tells you the amplitude.The period is how many times it makes a complete cycle in one cirlce. So the sine or cosine function- 2pi/b or 2pi/period=b. Tangent function = pi/b which also = period.(talking about how much horizontal space it takes up).
When written y=asin(b(x-c)+d c is A PHASE or HORIZONTAL SHIFT.