Diketahui F(x) : sin 2x - 1/2 cos x Tentukan nilai dari f'(x) π/2?

f(x) = sin 2x - 1/2 cos x
f'(x) = 2.cos 2x - 1/2 .(-sin x)
f'(x) = 2cos 2x + 1/2 sin x
f'(pi/2) = 2cos (2.pi/2) + 1/2 sin (pi/2)
f'(90°) = 2cos 180° + 1/2 sin 90°
f'(90°) = 2.(-1) + 1/2 .(1) = -2 + 1/2 = -3/2