Buktikan jika y = cotan x, maka y' = -cosec2(kuadrat) x

Turunan

y = cot x
y = cos x/sin x
u = cos x -> u'= - sin x
v = sin x-> v' = cos  x

y' = u' v  - u v'/(v²)

y' = -sin x (sin x) - cos x(cos x) /(sin² x)
y'= (-sin² x - cos² x)/(sin² x)
y' = - (sin² x + cos² x) / sin² x
y' = - 1/sin² x
y' =- cosec² x