Question 595884
# 1


Simply start with g(x) = 3x^2 and replace 'x' with f(x). Then replace f(x) 
on the right side with x^2-5 and simplify.


g(x) = 3x^2


g(f(x)) = 3(f(x))^2


g(f(x)) = 3(x^2-5)^2


g(f(x)) = 3(x^4 - 10x^2 + 25)


g(f(x)) = 3x^4 - 30x^2 + 75


So the answer is choice A

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# 2


Same idea as in #1, but now in reverse.


f(x) = x^2 - 4


f(g(x)) = (g(x))^2 - 4


f(g(x)) = (-3x^2)^2 - 4


f(g(x)) = 9x^4 - 4


So the answer is choice C