Test Academy | Find the interval in which function f(x) = sinx+cosx, 0 ≤ x ≤ 2π is decreasing (-π/4, π/4), (-π/4, 5π/4), (π/4, -5π/4), (π/4, 5π/4)

Question

Find the interval in which function f(x) = sinx+cosx, 0 ≤ x ≤ 2π is decreasing

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