вычислите 1) arcctg 1-arctg √3-arccos (-1/2); 2) arcsin(-1/2)+arctg (-1/√3)-arcctg √3;  3) arcsin -1- 3/2 arccos 1/2+3arcctg (-1/√3); 4) -4*arcsin (-√2/2) +8 arccos (-√2/2) -15*arctg √3/3

1)π/4-π/3-2π/3=-3π/42)-π/6+2π/3-π/6=π/33)-π/2-3/2*π/3+3*5π/6=-π/2-π/2+5π/2=3π/24)-4*(-π/4)+8*3π/4-15*π/6=π+6π-2,5π=4,5π