(1.5Đ) TÌM X B. X2 – 4X + 3= 0A. X2 – 4 = 0X2 – X – 3X + 3= 0 0.25X2 –...

Bài 2

: (1.5đ) Tìm x

b. x

²

– 4x + 3= 0a. x

²

– 4 = 0x

²

– x – 3x + 3= 0 0.25x

²

– 2

²

= 0 0.25x(x – 1) – 3(x -1) = 0(x – 2)(x +2) = 0 0.25Vậy (x – 2) = 0 hoặc (x +2) = 0 0.25(x – 1)(x – 3) = 0 x = 2 x = -2 0.25Vậy (x – 1) = 0 hoặc (x -3) = 0 x = 1 x = 3 0.25