5arccos 1/2+3 arccos(-√2/2)

Question

5arccos 1/2+3 arccos(-√2/2)

Answer 1

5arccos 1/2+3 arccos(-√2/2)=5*П/3+3(П/4+П/2)=П(5/3+3/4+3/2)=47П/12

Answer 2

5arccos 1/2+3 arcsin(-√2/2)=5*pi/3-3*pi/4=20pi/12-9pi/12=11pi/12