If f(x) is a function whose domain is [-1, 9] and g(x) = f(x^2), then the domain of g(x) is an interval of what width?
I think the answer is 81, but its wrong.
g(x) = f(x^2)
g(-1) = f( [-1]^2) = f(1)
And
g(9) = f(9^2) = f(81)
The interval is [ 81 - 1 ] = 80 units wide
