1) x²-8x-2√(x²-8x) - 3 = 0 ;замена t = √(x²-8x) ≥ 0 t² -2t -3 =0;t₁ = -1 не решение.t₂ =3√(x²-8x) =3 ;(x²-8x) =3² ;x²-8x -9 = 0 ;x₁ = -1;x₂ =9.ответ : { -1 ; 9} .2) - 4sinx/3cosx/3 = 1 ;-2sin2*x/3 = 1 * * * * * sin2α =2sinα*cosα * * * * *sin2x/3 = -1/2 ;2x/3 = (-1)^(n+1)π/6 +π*k ; x = 3/2( (-1)^(n+1)π/6 +π*k) ;x =(-1)^(n+1)π/4 +3π/2 ;k∈Z.ответ : (-1)^(n+1)π/4 +3π/2 ;k∈Z.