Question

[hoàng anh minh]

Phân tích các đa thức sau thành nhân tử.

a/ 3a +3b – a^2 – ab

b/ x2^ + x + y^2 – y – 2xy

c/ - x^2 + 7x – 6

d/ 5x^3y – 10x^2y^2 + 5xy^3

e/ 2x2+7x – 15

g/ x^2 -2x+2y-xy

h/ x +4x 16 +4 - 16+4y^2

Answer 1

[I don't need you]

a) 3a +3b -a²-ab

= 3.(a+b) -a.(a+b)=(3-a).(a+b)

b) x² +x +y²-y-2xy

=(x² - 2xy+y²) +(x-y)

=(x-y).(x-y+1)

c) -x² +7x -6

= -x² + x +6x-6

= x.(1-x) -6.(1-x) = (1-x).(x-6)

d) 5x³y -10x²y² +5xy³

= 5xy.(x² -2xy +y²) = 5xy.(x-y)²

e) 2x² +7x -15

= 2x² -3x +10x -15

=x.(2x-3) + 5.(2x-3)

=(2x-3).(x+5)

g) x² -2x +2y -xy

=x.(x-2)-y.(x-2)

=(x-y).(x-2)

h) bn go lai de ho mk dc k?