Some needed trig identities:

Trig Derivatives Graph y 1 = sin x and y 2 = nderiv (sin x) What do you notice?

Proof Algebraically (use trig identity for sin(x + h))

Proof Algebraically 0 1

Trig Derivatives Graph y 1 = cos x and y 2 = nderiv (cos x) What do you notice?

Proof Algebraically (use trig identity for cos(x + h))

Proof Algebraically 0 1

Other Trig Derivatives (quotient rule) (trig id cos 2 x + sin 2 x = 1)

Other Trig Derivatives (quotient rule)

Other Trig Derivatives (quotient rule)

Other Trig Derivatives (quotient rule)

Example Find an equation of the tangent line to the function f(x) = sec x at the point (slope)

Example Find the second derivative of y = csc x. (Product rule)