Functions

• Jul 9th 2009, 10:33 AM
A Beautiful Mind
Functions
I don't know where I'm going with this. I think my reasoning is out of whack, can someone please explain this to me?

http://img3.imageshack.us/img3/4803/43706846.jpg
Alright, so when f(x)=3, the x is a 1. And when x is a one over at the g(x) side where x is, it's a -1. So -1 x 3 = -3...B.
• Jul 9th 2009, 10:41 AM
Kasper
Quote:

Originally Posted by A Beautiful Mind
I don't know where I'm going with this. I think my reasoning is out of whack, can someone please explain this to me?

http://img3.imageshack.us/img3/4803/43706846.jpg
Alright, so when f(x)=3, the x is a 1. And when x is a one over at the g(x) side where x is, it's a -1. So -1 x 3 = -3...B.

We aren't looking for when \$\displaystyle f(x)=3\$, we are looking for the value of \$\displaystyle f(x)\$ AT \$\displaystyle x=3\$ Look at the table, and at \$\displaystyle x=3\$ we see that \$\displaystyle f(x)=2\$ which means that \$\displaystyle f(3)=2\$. Now because we have \$\displaystyle g(f(3))\$, we need to find \$\displaystyle g(x)\$ AT \$\displaystyle f(3)=2\$. So the question is essentially asking for \$\displaystyle g(2)=?\$

Looking at the table we see that \$\displaystyle g(f(3))=g(2)=-3\$ which is answer choice B.

Is another way to look at it.
• Jul 9th 2009, 10:44 AM
A Beautiful Mind
Nah, I got it. Thanks. ;)