Question

РЕШИТЕ УРАВНЕНИЯ
1)x^2/12+x=3x/12+x
2)x^2-2x=x-4/x+4
3)3x^2-5x-2/2-x=0

Answer 1

1) х^2(12 + x ) = 3x( 12 + x )
12x^2 + 3x^3 = 36x + 3x^2
x^3 + 12x^2 - 3x^2 - 36x = 0
x^3 + 9x^2 - 36x = 0
x( x^2 + 9x - 36) = 0
x = 0  x^2 + 9x - 36= 0
          D = 81+144 = 225=15^2
          x1 = 3   x2 = -12