establish the formulas d/dx sin x = cos x and d/dx(cosx)=−sinx by graphical treatment, numerical estimations of the limits and informal proofs based on geometric constructions
3.1.6
use trigonometric functions and their derivatives to solve practical problems
3.1.9
apply the product, quotient and chain rule to differentiate functions such as xe^x, tanx,1/x^n, x sinx, e^(−x)sinx and f(ax-b)
