Question

Разложить на множители квадратный трёхчлен:
1)-6х²+7х-2

2)-4х²-7х+2

Answer 1

1) - 6x^2 - 7x - 2 = -(6x^2 + 7x +2) = - 6(x + 1/2)·(x+ 2/3)= = - 2·(x+1/2)·3(x+2/3) = -(2x+1)·(3x+2).

D = 49 - 48 = 1;
 x= -1/2;
x = - 2/3.
2) - 4x^2 - 7x + 2 = - (4x^2 + 7x - 2) = - 4(x +2)(x- 1/4) =
= -(x+2)·4(x - 1/4) = - (x+2)(4x - 1) = (x+2)(1 - 4x).
D = 49 + 32 = 81= 9^2;
x = 1/4;
 x= - 2.