Question

π rad = 180° X rad = 90° Quando representa X em rad?

Answer 1

π rad — 180°
x rad — 90°

180x = 90π
x = 90π/180
x = π/2 rad

Answer 2

π rad ====180
    X  ===== 90

        90.π rad              π rad
X = ---------------- =  --------------             <<< Resposta
          180                       2