(a) Graph the function $f(x)=\sin x-\frac{1}{1000} \sin (1000 x)$ in the
viewing rectangle $[-2 \pi, 2 \pi]$ by $[-4,4] .$ What slope does the graph appear to have at the origin?
(b) Zoom in to the viewing window [-0.4,0.4] by [-0.25,0.25] and estimate the value of $f^{\prime}(0) .$ Does this agree with your answer from part (a)?
(c) Now zoom in to the viewing window [-0.008,0.008] by $[-0.005,0.005] .$ Do you wish to revise your estimate for $f^{\prime}(0) ?$