Diketahui y = x sec x² Ditanya dy/dx

jawab

y = x . sec x² 

u = x²
du/dx  = 2x

t = sec u
dt/du = sec u. tan u

dt/dx = dt/du. du/dx
dt/dx = sec x². tan x². 2x

y =  x. sec x²
y = u . t
y' = u' t + u t'
y' = sec x² + x . sec x². tan x². 2x
y' =  sec x² + 2x² . sec x². tan x²