Question

If `f(x) = x^2 - x` and `g(x) = 3x + 1` how do you find `g(f(sqrt2))`?

Answer 1

`7-3sqrt2`

Explanation:

`f(color(red)(sqrt2))=(color(red)(sqrt2))^2-color(red)(sqrt2)=2-sqrt2`

`"to evaluate " g(f(sqrt2)))`

`"substitute " f(sqrt2)" into " g(x)`

`rArrg(f(sqrt2)))=3(2-sqrt2)+1`

`color(white)(rArrg(f(sqrt2x)))=6-3sqrt2+1`

`color(white)(rArrg(f(sqrt2x)))=7-3sqrt2`