Question

cos (2П-x)+sin(П:2+x)=

Answer 1

по формулам приведения
cos(2π-x)=cosx
sin((π/2)+x)=cosx
cosx+cosx=√2
2cosx=√2
cosx=(√2)/2
x=+-(arccos(√2)/2)+2πn, n∈Z
x=+-(π/4)+2πn, n∈Z