Question

Let f(x) = 9x - 2 and g(x) = -x + 3. Find f(g(x)).

answer choices

-9x - 2

-9x + 5

-9x + 25

-9x + 27

Answer 1

\(f(\color{blue}{g(x)}) = f(\color{blue}{-x+3})=9(\color{blue}{-x+3})-2=-9x+27-2=-9x+25\)

Answer 2

all I did was plug in the function \(g(x)\) where ever I saw a \(x\) in \(f(x)\)

Answer 3

but wouldn't that change the function

Answer 4

we are taking two functions and making a third function out of them

Answer 5

we have three operations with functions \(f+g. f*g, f\cdot g\) the last being composition

Answer 6

so yes just as adding two functions changes things, so does composing two function.

Answer 7

just like 3+4=7 changes 3, and 4 into 7

Answer 8

ohh i get it now thank you!!

Answer 9

have you seen the human centipede movie? or know about it? (if not do NOT google it)

Answer 10

anyway this is how I explain composition of functions to students:)