You need to use the Product Rule of Differentiation. Given the product of two functions f(x) and g(x) in the form
y = f(x) * g(x), then the derivative of y, which is written as y', can be found using the Product Rule, which is
f'(x) * g(x) + f(x) * g'(x), where f'(x) and g'(x) are the derivatives of f(x) and g(x), respectively.
Let f(x) = x³ and g(x) = sin(x)
You can find the derivative of f(x) using the Power Rule of Differentiation.
f'(x) = 3x²
The derivative of g(x) = cos(x)