bang bantu nomor 8,9,10 cepat ya pliss... kurang paham soalnya.

jawab

8)  f(x) =  sin(5x - π)
u = 5x
du /dx= 5 

y = sin u
dy./du = cos u

y ' = dy/du. du/dx = cos u  ( 5)
y' = 5 cos u
y' = 5 cos (5x - π)


9. f(x) = 3 cos (2x + π)
f '(x) = 3(2) (- sin (2x +π) 
f '(x) = - 6 sin (2x + π)

10. f(x)= 2 cos (2π - 3x)
f'(x) = 2(-3) (-sin (2π - 3x))
f'(x) = 6 sin (2π - 3x)