Question

几个初二上学期的分解因式的题目

(a-b)的平方+4ab (p-4)(p+1)+3p 4xy的平方-4x的平方y-y的立方 xy-xz+y-z
(x+y)的平方-4（x+y)

Answer 1

1:（a-b）^2+4ab=a^2+b^2-2ab+4ab=a^2+b^2+2ab=(a+b)^2
2:p-4）（p+1)+3p=p²-3p-4+3p=p²-4=(p+2)(p-2)
3:4xy^2-4x^2y-y^3=y(4xy-4x^2-y^2)=-y(4x^2-4xy+y^2)=-y(2x-y)^2
4:xy-xz+y-z =y（x+1）-z（x+1）=(y-z)(x+1)
5:(x+y)^2-4(x+y-1)=(X +Y)^2-4(X+Y)+4=[(X+Y)-2]^2=(X+Y-2)^2

Answer 2

1:（a-b）^2+4ab=a^2+b^2-2ab+4ab=a^2+b^2+2ab=(a+b)^2
2:(p-4)p+1)+3p=p²-3p-4+3p=p²-4=(p+2)(p-2)
3:4xy^2-4x^2y-y^3=y(4xy-4x^2-y^2)=-y(4x^2-4xy+y^2)=-y(2x-y)^2
4:xy-xz+y-z =x(y-z)+(y-z)=(x+1)(y-z)
5:(x+y)^2-4(x+y)=(x+y)(x+y-4)

Answer 3

1)=(a+b)^2;
2)=(p+2)(p-2);
3)=-y(2x-y)(2x-y);
4)=(x+1)(y-z);
5)=(x+y)(x+y-4);