1.原式
= a(x-y)-b(x-y)
= (a-b)(x-y)
2.原式
= a(x^2+y^2)+b(x^2+y^2)
= (a+b)(x^2+y^2)
3.原式
= a(b-1)+b-1
= (a+1)(b-1)
4.原式
= ab-b+a-1
= b(a-1)+a-1
= (b+1)(a-1)
5.原式
= x(x+y)-3y(x+y)
= (x-3y)(x+y)
x^2表示x的平方.
1.原式
= a(x-y)-b(x-y)
= (a-b)(x-y)
2.原式
= a(x^2+y^2)+b(x^2+y^2)
= (a+b)(x^2+y^2)
3.原式
= a(b-1)+b-1
= (a+1)(b-1)
4.原式
= ab-b+a-1
= b(a-1)+a-1
= (b+1)(a-1)
5.原式
= x(x+y)-3y(x+y)
= (x-3y)(x+y)
x^2表示x的平方.