(cos2x +sinx)/√sin(x -π/4) =0 ⇔ { cos2x +sinx =0 ; sin(x -π/4) >0 .решаем уравнение cos2x +sinx =0 ; * * * cos2x +cos(π/2 -x) =0 ⇔2cos(x/2+π/4)*cos(3x/2 -π/4) =0 * * *или 1-2sin²x +sinx =0 ;2sin²x -sinx -1 =0 ;[sinx =1 ; sinx = -1/2 .[ x=π/2 +2πn ; x = -π/6+2πn ; x = 7π/6+2πn , n∈Z.Из этих корней выбираем те которые удовл. условию sin(x-π/4) >0.Если :------а) x=π/2 +2πn ⇒ x - π/4 = π/2 +2πn -π/4= 2πn+π/4 ;sin(x - π/4) = sin(2πn+π/4 )=sinπ/4 =√2/2 >0.б) x = -π/6+2πn ⇒ x - π/4 = -π/6+2πn -π/4 =2πn - 5π/12 ;sin(x - π/4) =sin(2πn- 5π/12) = - sin5π/12 < 0 →не корень. в) x= 7π/6+2πn ⇒ x - π/4 = 7π/6+2πn-π/4= 2πn+11π/12 ;sin(x - π/4) =sin(2πn +11π/12) =sin11π/12 > 0 .ответ : π/2 +2πn ; 7π/6+2πn , n ∈ Z.