Final answer:
To simplify the expression 9sec^2(x)-9 to a single trig function with no denominator, use the Pythagorean identity to rewrite it as 9tan^2(x).
Step-by-step explanation:
To simplify the expression 9sec2x-9 to a single trig function with no denominator, we can use the Pythagorean identity which states that sec2(x) = 1 + tan2(x). Using this identity, we can rewrite the expression as:
9(1 + tan2(x)) - 9
Expanding and simplifying:
9 + 9tan2(x) - 9
Which simplifies to:
9tan2(x)