X y+y^2/18x*6x/x+y при x = 6.9 y= -9.3

x^3 + x^2 - 9x - 9 = 0  x^2 (x + 1) - 9(x + 1) = 0  (x^2 - 9)(x + 1) = 0  x + 1 = 0  x₁ = - 1 x^2 - 9 = 0  x^2 = 9  x₂ = - 3 x₃ = 3  ---------------------------- 2x^3 + 8x - x^2 - 4 = 0  2x (x^2 + 4) - 1(x^2 + 4) = 0  (x^2 + 4)(2x - 1) = 0  x^2 + 4 = 0  x^2 = - 4 ==> ∅ 2x - 1 = 0  2x = 1  x = 0,5 ---------------------------------------- 3x^3 - x^2 + 18x - 6 = 0  x^2 (3x - 1) + 6(3x - 1) =  0 (3x - 1)(x^2 + 6) = 0  x^2 + 6 = 0  x^2 = - 6  x ==> ∅ 3x - 1 = 0  3x =  1 x = 1/3