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Find `gof` and `gof` when `f: R->R` and `g: R->R` is defined by `f(x)=2x+x^2` and `g(x)=x^3`

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`f(x) = 2x + x^2` and `g(x)=x^3 `
Now, `gof(x) = g(f (x)) `
`=g(2x + x^2) `
`=x^6 + 8x^3 + 6x^5 + 12x^4 `
and `fog(x)=f(g(x))= f(x) `
`=> fog(x) = 2x^3 + x^6`
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