jika y= 2x cos x maka dy/dx= ?

jawab

y = 2x cos x
u = 2x
u' = 2

v= cos x
v' = -sin x

y = u v
y' = u'v+ uv'
y' = 2(cos x) + 2x(-sin x)
y' = 2 cos x - 2x sin x