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