Final answer:
To show that d²y/dx² = -2sin(2x), differentiate y = sin(x)cos(x) twice with respect to x. First, find the first derivative using the product rule, then differentiate the first derivative with respect to x again. The resulting equation is d²y/dx² = -2sin(2x).
Step-by-step explanation:
To show that d²y/dx² = -2sin(2x), we need to differentiate y = sin(x)cos(x) twice with respect to x.
We start by finding the first derivative of y using the product rule:
dy/dx = (cos(x))(cos(x)) + (sin(x))(-sin(x)) = cos²(x) - sin²(x) = cos(2x)
Next, we differentiate dy/dx with respect to x again:
d²y/dx² = d(cos(2x))/dx = -2sin(2x)
Therefore, d²y/dx² = -2sin(2x), which proves the given equation.