I have total forgotten how to do these, f(x)=4x , h(x)=x+5

what is (f+h)(x)? Thank you everybody.

Printable View

- Sep 1st 2008, 04:52 PMOnMyWayToBeAMathProffesorpre-calculus help please
I have total forgotten how to do these, f(x)=4x , h(x)=x+5

what is (f+h)(x)? Thank you everybody. - Sep 1st 2008, 05:01 PMChop Suey
$\displaystyle (f+h)(x) = f(x) + h(x)$

- Sep 1st 2008, 07:09 PMOnMyWayToBeAMathProffesor
I knew it was something simple like that, thank you very much for unlocking all of my past knowledge but I still can not remember what these kind of problems of called, are they conjunctions?

- Sep 1st 2008, 07:21 PMOnMyWayToBeAMathProffesor
I am sorry, but another quick question, $\displaystyle f(x)=4x$ , $\displaystyle h(x)=x+5$ , $\displaystyle g(x)=x^2$

then $\displaystyle f(g(h(x)))$ = $\displaystyle 16x^2+5$ or $\displaystyle 4(x+5)^2=4x^2+40X+100$ - Sep 1st 2008, 07:26 PM11rdc11
Nope try again.

Should be,

$\displaystyle 4x^2 + 40x +100$ - Sep 1st 2008, 07:29 PMOnMyWayToBeAMathProffesor
Thank you, I saw my error and edited my last post, I made a very foolish mistake. the answer is actually $\displaystyle 4(x+5)^2=4x^2+40X+100$ like you said. Thanks again.

- Sep 1st 2008, 07:31 PM11rdc11
No problem glad to help anytime.