Question

因式分解 用完全平方公式

(1)1-x^2-2xy-y^2
(2)x^2+4ax+4a^2-y^2

Answer 1

-x^2-2xy-y^2= 1-（x+y）^2=(1-x-y)(1-x+y)
x^2+4ax+4a^2-y^2 =(x+2a)^2-y^2=(x+2a+y)(x+2a-y)

Answer 2

1)1-x^2-2xy-y^2
=1-(x^2+2xy+y^2)
=1-(x+y)^2
=(1+x+y)(1-x-y)

(2)x^2+4ax+4a^2-y^2
=(x+2a)^2-y^2
=(x+2a+y)(x+2a-y)

Answer 3

1-x^2-2xy-y^2=1-（x^2+2xy+y^2）=1-（x+y）^2=(1-x-y)(1+x+y)

x^2+4ax+4a^2-y^2=(x^2+4ax+4a^2)-y^2=（x+2a)^2-y^2=(x+2a-y)(x+2a+y)

Answer 4

1-x^2-2xy-y^2=1-（x+y)^2=(1+x+y)(1-x-y)
x^2+4ax+4a^2-y^2 =(x+2a)^2-y^2=(x+2a-y)(x+2a+y)