It is often useful to know that, when x is measured in radians, sin x ≈ x for numerically small values of x. We will see why the approximation holds. The approximation error is less than 1 in 5000 if |x | < 0.1.

a. With your grapher in radian mode, graph y = sin x and y = x together in a viewing window about the origin. What do you see happening as x nears the origin?

b. With your grapher in degree mode, graph y = sin x and y = x together about the origin again. How is the picture different from the one obtained with radian mode?