The function f(x) = tan⁻¹(sin x + cos x) is an increasing function in
(0, π/2)
(-π/2, π/2)
(-π/4, π/4)
(-π/2, π/4)
Correct answer: (-π/2, π/4)
Solution
The function f(x) = tan⁻¹(sin x + cos x) is increasing in the interval (-π/2, π/4) because the derivative of the function is positive in this range, indicating that the function's output increases as x increases.