Arccos (-[latex]\sqrt{}\frac{2}{2}[/latex] ) - arcsin(-1) = 

arccos (- ) - arcsin(-1) = 3П/4+П/2=5П/4

[latex]arccos(- \frac{ \sqrt{2} }{2} )-argsin(-1)= \frac{3 \pi }{4} + \frac{ \pi }{2} = \frac{5 \pi }{4} [/latex]