Hey guys could you just check if i did this right please?

q: Differentiate using the chain rule

a:

$\displaystyle

y(x) = cos(5x^2+8)

$

$\displaystyle

u = (5x^2+8)

$

$\displaystyle

du/dx = 10x

$

$\displaystyle

dy/du = -sin(u)

$

$\displaystyle

dy/dx = -sin(10x)

$