Answer: Choice C
F(x) = x+4 and G(x) = x^3-1
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Explanation:
Let's try choice A to see if it works or not
G(x) = (x+4)^3
G( F(x) ) = ( F(x)+4 ) ^3 .... replace every x with F(x)
G( F(x) ) = ( x-1+4 ) ^3 .... plug in F(x) = x-1
G( F(x) ) = (x+3)^3
This isn't the same as (x+4)^3 - 1. You can confirm this with a graph or a table of values. We cross choice A off the list.
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Let's try choice B
G(x) = x+4
G( F(x) ) = F(x)+4
G( F(x) ) = x^3-1 + 4
G( F(x) ) = x^3 + 3
Similar to choice A, this isn't the same as (x+4)^3-1. We can cross this off the list as well.
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Now choice C
G(x) = x^3 - 1
G( F(x) ) = ( F(x) )^3 - 1
G( F(x) ) = (x+4)^3 - 1
We found the final answer.
