Question

[Văn Thanh 1]

1. Phân tích đa thức sau thành nhân tử 

a) 14x^2y - 21xy

b) -x^2 + 6x - 9 

c) 3x^2 - 6xy + 3y^2 - 27 

Answer 1

[︻̷̿┻̿═━დდDarknightდდ]

a,\(14x^2y-21xy=7xy.\left(2x-3\right)\)

b,\(-x^2+6x-9=-\left(x^2-6x+9\right)=-\left(x-3\right)^2\)

c,\(3x^2-6xy+3y^2-27=3.\left(x^2-2xy+y^2-9\right)=3.\text{[}\left(x-y\right)^2-3^2\text{]}=3.\left(x-y-3\right).\left(x-y+3\right)\)

Answer 2

[✫°”˜˜”°♌️NTTH♌️°”˜˜”°✫(๖team lion๖)]

a) 14x²y - 21xy

= 7xy (2x - 3)

b) -x² + 6x - 9

= -(x² - 6x + 3²)

= -(x - 3)²

c) 3x² - 6xy + 3y² - 27

= 3 (x² - 2xy + y² - 9)

= 3 [(x² - 2xy + y²) - 9]

= 3 [(x - y)² - 3²]

= 3 (x - y - 3) (x - y + 3)

#Học tốt!!!

~NTTH~