Question

Can anybody help me and explain how to calculate it?​

Answer 1

`(\pi )/(4)`

Explanation:

1. note, that

`arcsin(1)/(2)=(\pi)/(6);arcsin(√(2))/(2)=(\pi)/(4);arcsin1=(\pi )/(2);arcsin(√(3))/(2)=(\pi)/(3)`

2. after the substitution:

`(\pi)/(6)+(\pi )/(4)- (\pi )/(2) + (\pi )/(3)=(\pi )/(4).`