1
а)-√2/2;б)√3;в)1/2;г)-1
2
а)t=(-1)^n*π/3+πn,n∈z
б)t=+-3π/4+2πn,n∈z
3
cost:cost/sint+sin(π+t)=cost*sint/cost-sint=sint-sint=0
4
(sint/cost+cost/sint)*sint:sint/cost=(sin²t+cos²t)/(sintcost)*sint*cost/sint=1/sint
5
5√3sin(1080+60)+4cos(720+60)-ctg²30=5√3sin60+4cos60-ctg²30=
=5√3*√3/2+4*1/2-(√3)²=15/2+2-3=6,5