Question

Phân tích đa thức thành nhân tử:

a) 3x²y - 6xy² + 3y²

b) a² - b² + 2a + 2b

c) x² + 6x + 9 - y²

d) x² - 9x + 20

Answer 1

Answer 2

a)3y(x² -2xy+y)

b)=(a+b)(a-b)+2(a+b)

=(a+b)(a-b+2)

 

Answer 3

b)

Answer 4

c)

Answer 5

d)

Answer 6

c)=(x+3)²-y²

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

d) x² - 9x + 20

=x²-4x-5x+20

=x(x-4)-5(x+4)

=x(x-4)-5(x-4)

=(x-4)(x-5)

 

Answer 7

a) 3x²y-6xy²+3y²
= 3y(x²-2xy+3y)
b) a²-b²+2a+2b
= (a+b)(a-b)+2(a+b)
= (a+b)(a-b+2)
c) x²+6x+9-y²
= (x+3)²-y²
= (x+3-y)(x+3+y)
d) x²-9x+20
= x²-4x-5x+20
= x(x-4)-5(x-4)
= (x-5)(x-4)