a)arcisn0=0;
arccos0=π/2, так как cos(π/2)=0
arcsin0+arccos0=[b]π/2[/b]
б)
arcisn(-sqrt(2)/2)=-π/4, так как sin(-π/4)=sqrt(2)/2 и (-π/4) ∈ [-π/2;π/2];
arccos(1/2)=π/3, так как cos(π/3)=1/2 и (π/3) ∈ [0;π]
arcsin(-sqrt(2)/2)+arccos(1/2)=(-π/4)+(π/3)=[b]π/12[/b]