### Home > PC > Chapter 9 > Lesson 9.2.1 > Problem 9-70

9-70.

Let

*s*(*x*) = sin*x*. Homework Help ✎Find the exact value of the average rate of change of

*s*(*x*) from*x*=to *x*=. Write the expression for the average rate of change of

*s*(*x*) from*x*=to *x*=*h*.Use the fact that sin(

*A*+*B*) = sin*A*cos*B*+ cos*A*sin*B*to show that the expression in part (b) can be written as.

Substitute values for the trigonometric expressions and simplify.