Thursday, September 13, 2007

The Work of the Day (September 13, 2007)

Hey guys we sure missed you today! I hope that you both are feeling better and i hope you get this blog in time to make use of it. I know you both are dying to get this info... Love you guys and see you tomorrow! = )
-Max Chellemi
Here is the Question of the day!

True or false...sorry Rachel ; ) hehe

The function f(x) = cos(x) - sin(x) is increasing in


Lets analyze the question. We need to be able to visualize the graphs of sin(x) and cos(x). We also need to know that we are looking to see that the value of the output {f(x)} is increasing in value between the given parameters. Remember when the function is said to be increasing there may be no decreasing values in the output of the function between the given parameters.

Ok we know that the graph of sin(x) looks like

We also know that the graph of cos(x) looks like








Ok sorry for the layout issues but you don't know how hard this is...or how slow i am haha but i am trying. Ok so now that we have the graphs we can start tho think about this.

alright. We don't care about any part of the function that has an x less than zero or greater than π/2. We observe that the two functions cross at pi/4 and are the farthest apart as we approach π/2.

Graphically we can already see that the function doesn't increase the entire time but now we must examine it numerically to solidify our argument. Lets pick two easily identifiable points and check our hypothesis with a table.

x

f(x) = cos(x) - sin(x)

0

1

π/4

0


We need go no further ladies. As clearly indicated in the table above we increased the "x" value and the "y" value decreased, ergo the function is not solely increasing between


Today’s lesson talked about the Corollary to the Theorems that we received yesterday concerning continuity (the three things). The theorem reads: suppose “g” is continuous at “a” and “f” is continuous at g(a), then the function is continuous.

I am having some real trouble conjuring up the graph right now but i will try and get it up in a little while along with an explanation.


I hope this was helpful for you guys! Get well! I mean it!
Night
-Max Chellemi


3 comments:

Emily said...

max, thank you so much! you are my hero!!!!

Rumidog said...

Max,

Excellent! Excellent! Excellent!


You have set a high standard for the following acts.

Feel free to share any tricks that you learned in creating this post. That sounds like a post of its own.

Again, thank you for moving us forward.

Rachel W. said...

Thank you so much Max. This is spectacular!