将下列各式因式分解: (1)4a2 y2 -16a2 x2 ; (2)2a2 x-2ax+1/2x; (3)3x(x−y)3 -6y(y−x)2 ; (4)1/4(a+b)2 +(a+b)+1.

问题描述:

将下列各式因式分解:
(1)4

a
y
-16
a
x

(2)2
a
x-2ax+
1
2
x;
(3)3x(x−y
)
-6y(y−x
)

(4)
1
4
(a+b
)
+(a+b)+1.

(1)4

a
y
-16
a
x
=4a2(y2-4x2)=4a2(y+2x)(y-2x);
(2)2
a
x-2ax+
1
2
x=2x(a2-a+
1
4
)=2x(a-
1
2
2
(3)3x(x−y
)
-6y(y−x
)
=3(x-y)2[x(x-y)-2y]=3(x-y)2(x2-xy-2y);
(4)
1
4
(a+b
)
+(a+b)+1=[
1
2
(a+b)+1]2=(
1
2
a+
1
2
b+1)2