Х^2(3-х)(х+2)> 0 решить неравенство

У=  х² - 10 у = 4х + 11 подставим во второе уравнение  вместо у его у = 4х + 11 4х + 11 = х² - 10 х² - 4х - 10 - 11 = 0 х² - 4х - 21 = 0  d = b² - 4ac  d = 16 - 4 * 1 * (-21) = 16 + 84 = 100  x₁ = (4 + 10)/2 = 14/2 = 7 x₂ = (4 - 10)/2 = (-6)/2 = - 3 при  x₁ = 7   ищем  y₁ = 4 * 7 + 11 = 28 + 11 = 39     {7;   39} при   x₂ = - 3   ищем   y₂ = 4 * (- 3) + 11 = - 12 + 11 = - 1   {-3;   -1}  ответ:     {7;   39}   и  {-3;   -1}

Ну и 8: (1+8: (1-8: (1+4: (1-4: (1- =1993-1 8: (1+8: (1-8: (1+4: (1-4: (1- ) =1992 1+8: (1-8: (1+4: (1-4: (1- =1/249 8: (1-8: (1+4: (1-4: (1- =1/249-249/249 8: (8: (1-8: (1+4: (1-4: (1- =-248/249 1-8: (1+4: (1-4: (1-8х)) =8 * (-249/248) 1-8: (1+4: (1-4: (1-8х)) =-249/31 8: (1+4: (1-4: (1-8х)) =31/31+249/31 8: (1+4: (1-4: (1-8х)) =280/31 1+4: (1-4: (1-8х)) =8*(31/280) 1+4: (1-4: (1-8х)) =31/35 4: (1-4: (1-8х)) =31/35-35/35 4: (1-4: (1-8х)) =-4/35 1-4: (1-8х) =4 * (-35/4) 1-4: (1-8х) =-35 4: (1-8х) =1+35 4: (1-8х) =36 1-8х=1/9 8х=9/9-1/9 8х=8/9 х=1/9