The greatest and least values of (sin-1 x)2 + (cos-1 x)2 are a,b respectively

We have, sin−1⁡x2+cos−1⁡x2=sin−1⁡x+cos−1⁡x2−2sin−1⁡x⋅cos−1⁡x=π24−2sin−1⁡xπ2−sin−1⁡x=π24−πsin−1⁡x+2sin−1⁡x2=2sin−1⁡x2−π2sin−1⁡x+π28=2sin−1⁡x−π42+π216Thus, the least value is, π216 i.e. π28 and the greatest value is 2−π2−π42+π216 i.e. 5π24