The derivative of cosec x is
-
A.
tan x cosec x -
B.
-cot x cosec x -
C.
tan x sec x -
D.
-cot x sec x
Correct Answer: Option B
Explanation
(csc x = frac{1}{sin x})
Using the quotient rule,
(frac{mathrm d y}{mathrm d x} = frac{vdu – udv}{v^{2}})
= (frac{sin x (0) – 1 (cos x)}{(sin x)^{2}})
= (frac{- cos x}{sin^{2} x})
= ((frac{- cos x}{sin x}) (frac{1}{sin x}))
= (- cot x csc x)