Show all work please

12 Problem 4: [12.5 pts] Harper needs to evaluate the integral x2 - 9 dx but is unsure how to do so. A. [5 pts] Use the substitution x = 3 sec(0) to show Harper how to evaluate 12 x2 - 9 dx. Simplify your final answer. Hint: You may use the formulas derived in class for / sec(0) de, / csc(0) de, / tan(0) de, or / cot(e) de should one of them arise. You do not need to derive any of these results