Question

помогите срочно решить примеры ,1 3 6 11 15

Answer 1

скупой рыцарь
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15) √2sin²x -2cosx/2 = -√2cos²x ;
√2sin²x +√2cos²x =2cosx/2 ;
 √2(sin²x +√cos²x) =2cosx/2  ;
√2 =2cosx/2  ;
cosx/2 =√2/2 ;
x/2 =±π/4 +2π*k ;
x =±π/2 +4π*k , k∈Z.
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11) sin²x +2cos2x= - cos²x ;
cos2x = -1/2 ;
2x = ±2π/3 +2π*k ;
x = ±π/3 +π*k ,  k∈Z.
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6) √3sin²x +2sin3x= - √3cos²x ;
sin3x = - √3/2 ;
3x = (-1)^k*(π/3) +π*k ;
x = (-1)^k*(π/9) +π/3*k  , k∈Z.
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3) sin²x +2sin4x= - cos²x ;
sin4x = -1/2 ;
4x = (-1)^k*(π/6) +π*k ;
x = (-1)^k*(π/24) +π/4*k , k∈Z.
1) sin²x +sin2x= - cos²x ;
sin2x= - sin²x  - cos²x ;
sin2x= - (sin²x  + cos²x ) ;
sin2x = -1;
2x = -π/2 +2π*k ;
x =  -π/4 +π*k  , k∈Z.