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sandy524
find the critical points of f(x) = cos(x) − sin^2(x) on [0,2pi]
Critical points happen when the derivative is zero. So first find the derivative of f(x). Then set f'(x) equal to zero and solve for x. (You might want to use a unit circle to help you solve, especially since it covers the interval [0,2π].) These x values are your critical points. Do you need help finding the derivative?