turunan pertama fungsi f(x)= cos √x adalah...

turunan trigonometri
y = cos (√x)

u = √x= x¹/²
du/dx = 1/2 x⁻¹.² = 1/(2√x)

y = cos u
dy/du = - sin uu

y' = dy/dx
y' = dy/du. du/dx
y' = - sin u . 1/(2√x)
y' = (- sin √x)/(2√x)

y' = -1/(2√x) { sin (√x) }