Question

Solve the following inequality. Express the exact answer in interval notation, restricting your attention to 0 ≤ x ≤ 2π

Answer 1

         tan(x) ≥ 1
tan⁻¹(tan(x)) ≥ tan⁻¹(1)
                 x ≥ 45°
                 x ≥ ¹/₄π

Answer 2

Since tan is a strictly increasing function you just need to solve the equation tan x = 1 for 0<=x<=2pi. X is pi/4 this resulting into the final answer:
x E [pi/4, 2pi]