हिंदी

Find gof and fog, if f(x) = 8x^3 and g(x) = x^(1/3).

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प्रश्न

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

योग
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उत्तर

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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