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given that f(x) = 3x – 5 and g(x) = x3 – x, what is f(g(2))?
title
composition with cubic
your result
correct
difficulty
medium
your pace
0:01
others' pace
0:45
video explanation
text explanation
since g(x) is inside f(x), we first have to plug x = 2 into g(x), and then the output of g(2) will be the input of f(x).
g(x) = x3 – x
g(2) = (2)3 – 2 = 8 – 2 = 6
that's the output of g(2), so that's what we plug into f(x).
f(g(2)) = f(6) = 3(6) – 5 = 18 – 5 = 13
answer = (d)
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