• Sep 1st 2008, 04:52 PM
OnMyWayToBeAMathProffesor
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 PM
Chop Suey
\$\displaystyle (f+h)(x) = f(x) + h(x)\$
• Sep 1st 2008, 07:09 PM
OnMyWayToBeAMathProffesor
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 PM
OnMyWayToBeAMathProffesor
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 PM
11rdc11
Nope try again.

Should be,

\$\displaystyle 4x^2 + 40x +100\$
• Sep 1st 2008, 07:29 PM
OnMyWayToBeAMathProffesor
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 PM
11rdc11
No problem glad to help anytime.