Mohon dibantu beserta caranya ya Kurang mengerti dengan materi trigonometri. Trimakasih

jawab

1.

f(x) = sin⁶ (7x⁴ - 8)

u = 7x⁴ -8
du/dx = 28 x³

t = sin u
dt/du = cos u

y = t⁶
dy/dt =6t⁵

y' = dy/dx
dy/dx = dy/dt. dt/du. du/dx
y' = (6t⁵) (cos u) (28 x³)
y' = 6 sin⁵ (u). cos (7x⁴ - 8). (28x³)
y' = 6(28) x³  sin⁵ (7x⁴ -8) . cos (7x⁴ -8) 
y' = 168 x³  sin⁵ (7x⁴ -8 ) cos (7x⁴ -8)

2)
f(x) = cos⁴ (5x⁶-11)
f' (x) =  4. (30x⁵) cos³ (5x⁶ -11) (- sin (5x⁶ -11))
f' (x) =  -120 x⁵ cos³ (5x⁶ -11)  sin (5x⁶ -11)