Question

2, phân tích đa thức thành nhân tử  

a, x^2-3x+2                                      b , x^2+x-6

c, 3x^2-8x+4                                     d, 4x^2-4x-3

Answer 1

Answer 2

a) x² - 3x + 2

= x² - x - 2x + 2

= (x² - x) + (-2x + 2)

= x(x - 1) - 2(x - 1)

= (x - 1)(x - 2)

b) x² + x - 6

= x² - 2x + 3x - 6

= (x² - 2x) + (3x - 6)

= x(x - 2) + 3(x - 2)

= (x - 2)(x + 3)

c) 3x² - 8x + 4

= 3x² - 6x - 2x + 4

= (3x² - 6x) + (-2x + 4)

= 3x(x - 2) - 2(x - 2)

= (x - 2)(3x - 2)

Answer 3

d) 4x² - 4x - 3

= 4x² - 4x + 1 - 4

= (4x² - 4x + 1) - 4

= (2x - 1)² - 2²

= (2x - 1 - 2)(2x - 1 + 2)

= (2x - 3)(2x + 1)