Question

phân tích đa thức thành nhân tử

a/ x²-9x+8

b/ x²+6x+8

thank trước nha

Answer 1

a) x² - 9x + 8

= x² - 9x - 1 + 9

= (x² - 1) + (-9x + 9)

= (x + 1) (x - 1) - 9(x - 1)

= (x - 1) (x + 1 - 9)

= (x - 1) (x - 8)

b) x² + 6x + 8

= x² + 2x + 4x + 8

= (x² + 2x) + (4x + 8)

= x(x + 2) + 4(x + 2)

= (x + 2) (x + 4)

ok mk nha!!! 6476775758766925353464565645645765687687676976924563464554

Answer 2

a) x² - 9x + 8

= x² - 9x - 1 + 9

= (x² - 1) + (-9x + 9)

= (x + 1) (x - 1) - 9(x - 1)

= (x - 1) (x + 1 - 9)

= (x - 1) (x - 8)

b) x² + 6x + 8

= x² + 2x + 4x + 8

= (x² + 2x) + (4x + 8)

= x(x + 2) + 4(x + 2)

= (x + 2) (x + 4)