Derivatives by formula - other trignometric
Derivatives by formula - other trignometric
Last updated at August 2, 2026 by Teachoo
Transcript
Misc 25 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): (x + cos x) (x tan x) Let f (x) = (x + cos x) (x tan x) Let u = x + cos x & v = x tan x f(x) = uv So, f (x) = Using product rule f (x) = + Finding u & v u = x + cos x u = (x + cos x) = 1 sin x & v = x tan x v = (x tan x) = 1 sec2 x Now, f (x) = = + = (1 sin x) (x tan x) + (1 sec2 x) (x + cos x) = (1 sin x) (x tan x) (sec2 x 1) (x +cos x) = (1 sin x) (x tan x) tan2x (x + cos x) = tan2x (x + cos x) + (x tan x) (1 sin x)