Derivatives by formula - sin & cos
Last updated at August 11, 2026 by Teachoo
Transcript
Misc 16 Find the derivative of the following functions (it is to be understood that a, b, c, d, p, q, r and s are fixed non-zero constants and m and n are integers): cos x 1+ sin x Let f (x) = cos x 1 + sin x Let u = cos x & v = 1 + sin x So, f(x) = f (x) = Using quotient rule f (x) = 2 Finding u & v u = cos x u = sin x & v = 1 + sin x v = 0 + cos x = cos x Now, f (x) = = 2 = ( sin ) (1 + sin ) cos ( cos ) (1 + sin x ) 2 = sin (1 + sin ) cos2 (1 + sin x ) 2 = sin sin2 cos2 (1 + sin x ) 2 = sin ( + ) (1 + sin x ) 2 = sin (1 + sin x ) 2 = (sin + 1) (1 + sin x ) 2 = (1 + sin ) (1 + sin x ) 2 = 1 1 + sin Hence f (x) = +