Question

Let f(x) = 9x - 2 and g(x) = -x + 3. Find f(g(x)).
So far I have, f(g(x)) = f(-x+3) = 9x(-x + 3) -2 =
(-9x^2 + 27x) -2 - what am I doing wrong because I know I messed up somewhere.

Answer 1

f(-x+3) = 9x(-x + 3) -2
no! where did the extra 'x' come from ???
f(-x+3) = 9(-x + 3) -2
right??

Answer 2

because you just replace 'x' by -x+3

Answer 3

Oh gosh I feel stupid now. Thanks!

Answer 4

don't bother, silly mistakes do happen :)
welcome ^_^

Answer 5

oh, and since you are new here
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