If sin−1x=π5, for some x∈(−1,1), then find the value of cos−1x
The value of sin−1[cos(33π5)] is
(a) 3π5 (b) −7π5 (c) π10 (d) −π10
The value of cos−1(cos3π2) is
(a) π2 (b) 3π2 (c) 5π2 (d) 7π2