If y = sin(x) cos(x), then dy/dx = ?
Q1. If y = sin(x) cos(x), then dy/dx = ?
Answer: cos²(x) - sin²(x)
Explanation: Using product rule, dy/dx = d(sin(x)cos(x))/dx = sin(x)d(cos(x))/dx + cos(x)d(sin(x))/dx = sin(x)*(-sin(x)) + cos(x)*cos(x) = cos²(x) - sin²(x).