1 2sinycosy-2cos2ycosy-cosy=0 cosy*(2siny-2cos2y-1)=0 cosy=0⇒y=2πn,n∈z 2siny-2+4sin²y-1=0 4sin²y+2siny-3=0 siny=a 4a²+2a-3=0 D=4+48=52 a1=(-2-2√13)/8=-1/4-√13/4⇒sinx=-1/4-√13/4<-1 нет решения a2=-1/4+√13/4⇒sinx=-1/4+√13/4⇒x=(-1)^k*arcsin(-1/4+√13/4)+πk,k∈z 2 x²-2x-3≥0 x1+x2=2 U x1*x2=-3 x1=-1 U x2=3 x∈(-∞;-1] U [3;∞)
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12sinycosy-2cos2ycosy-cosy=0
cosy*(2siny-2cos2y-1)=0
cosy=0⇒y=2πn,n∈z
2siny-2+4sin²y-1=0
4sin²y+2siny-3=0
siny=a
4a²+2a-3=0
D=4+48=52
a1=(-2-2√13)/8=-1/4-√13/4⇒sinx=-1/4-√13/4<-1 нет решения
a2=-1/4+√13/4⇒sinx=-1/4+√13/4⇒x=(-1)^k*arcsin(-1/4+√13/4)+πk,k∈z
2
x²-2x-3≥0
x1+x2=2 U x1*x2=-3
x1=-1 U x2=3
x∈(-∞;-1] U [3;∞)