27. Let f(x) = x2(x3 + 1)4. What is the area under the graph of f over the closed interval [-1,1]?

 A. 0

B. 32/15

C. 62/15

D. 64/15

E. 32/5

 

 

Solution: The answer is B

 The area under the graph of f over the closed interval [-1,1] can be obtained by integrating f(x) with respect to x over the interval [-1,1]. That is, solve the following integral, 

 

Use the method of variable substitution, by letting u = x3 + 1, so that,