Keep getting the last 2 wrong:(
g(a-6) put in 'a-6' for 'x' in the g function
[6-(a-6)] / [6+(a-6)] = (12-a)/a
For the last one sub in x^2-6 for 'x' in the g function and see what you find.....
g (x^2 - 6) = 6 - (x^2 - 6) 12 - x^2
_____________ = _______
6 + (x^2 - 6) x^2