2cos²x+√3sinx+1=0
2-2sin²x+√3sinx+1=0
2sin²x-√3sinx-3=0
sinx=a
2a²-√3a-3=0
D=3+24=27
a1=(√3-3√3)/4=-√3/2⇒sinx=-√3/2⇒x=(-1)^(n+1)*π/3+πn
n=-2⇒x=-π/3-2π=-7π/3∉[-2π;-π/2]
n=-1⇒x=π/3-π=-2π/3∈[-2π;-π/2]
n=0⇒x=-π/3∉[-2π;-π/2]
a2=(√3+3√3)/4=√3⇒sinx=√3>1 нет решения
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