Question

Find the derivative of with respect to x: Y=-2x^3 sin(4x-1)

Answer 1

if y= a(x)*b(x)
dy/dx= a(x)*b'(x)+a'(x)*b(x)

Answer 2

u= 4x-1

d(sin(u)) = cos(u)
d(4x-1) = 4

Dx(sin(4x-1)) = 4 cos(4x-1) you can use that in your product rule as b'(x) if it helps....