Question

cos(2x-1)=-v2/2


Tgп/x=7



Sin2x=П/4

Ctgx=tgп/3

Answer 1

1
2x-1=-3π/4+2πn U 2x-1=3π/4+2πn
2x=1-3π/4+2πn U 2x=1+3π/4+2πn
x=1/2-3π/8+πn U x=1/2+3π/8+πn,n∈z
2
π/x=arctg7+πn
x=1/π*arctg7+1/n,n∈z
3
2x=arcsinπ/4+2πn U 2x=π-arcsinπ/4+2πn
x=1/2*atcsinπ/4+πn U x=π/2-1/2*arcsinπ/4+πn,n∈z
4
ctgx=√3
x=π/6+πn,n∈z