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Question
Find gof and fog, if f(x) = 8x3 and `g(x) = x^(1/3)`.
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Solution
f(x) = 8x3 and `g(x) = x^(1/3)`
∴ (gof)(x) = g(f(x))
= g(8x3)
= `(8x^3)^(1/3)`
= 2x
(fog)(x) = f(g(x))
= `f(x^(1/3))`
= `8(x^(1/3))^3`
= 8x
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