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Find `fog(2)` and `gof(1)` when: `f: R rarr R ;f(x)=x^2+8` and `g: R rarr R ;g(x)=3x^3+1.`

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`f(x) = x^2+8`
`g(x) = 3x^3+1`
Now, `fog(2) = f(g(2)) = f(3(2^3)+1) = f(25) =25^2+8 = 625+8 = 633`
`gof(1) = g(f(1)) = g(1^2+8) = g(9) = 3(9)^3+1 = 2187+1 = 2188`.
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