bntu jawab ya kakk dari nomor 2 sampe 4

2. turunan
y =  cos³ (5 - 4x)
u = 5- 4x
du /dx = - 4

t = cos u
dt/du = - sin u

y = t³
dy/dt = 3 t²

dy/dx = dy/dt. dt/du.du/dx
dy/dx = 3t². (-sin u). (-4)
dy/dx = - 12 cos² (5-4x) sin (5x- 4)

3.turunan
y = cos (3/x)
u = 3/x --> du/dx = -3/x²
y = cos u  -->dy/du  = - sin  u

dy/dx = dy/du, du/dx
dy/dx= (- sin u)( -3/x²)
dy/dx =3/x² . sin(3/x)


4.turunan y =tan(cos x)

u = cos x
du/dx = - sin x

y = tan u
dy/du = sec² u

dy/dx = dy/du.du/dx
dy/dt = sec² u .(-sin x)
dy/dt = - sec² (cos x). sin x