The question is: choose one interesting problem from the test of medium difficulty that was not assigned. Describe why you find it interesting. Then solve the problem, including a careful and complete explanation of all steps to your solution. This is the problem I picked and it has the answer already just need to answer the question and steps. Thank you

Using Formulas In Exercises 83, 84, 85, and 86, find the indefinite integral by using the appropriate formula from Exercises 79, 80, 81, and 82. 83. sin' a da Answer + 1 15 cos x (3 sin x + 4 sin x + 8) + C