1、b^3(x-2)+b(2-x)
=b^3(x-2)-b(x-2)
=b(x-2)(b^2-1)
=b(x-2)(b+1)(b-1)
2、-1\4x^4+9y^2
=(3y+1/2x^2)(3y-1/2x^2)
3、(x+2)^2-9
=(x+2+3)(x+2-3)
=(x+5)(x-1)
4、(x+a)^2-(y+b)^2
=(x+a+y+b)(x+a-y-b)
=(x+y+a+b)(x-y+a-b)
5、25(a+b)^2-4(a-b)^2
=[5(a+b)+2(a-b)][5(a+b)-2(a-b)]
=(7a+3b)(3a+7b)
6、0.25(x+y)^2-0.81(x-y)^2
=[0.5(x+y)+0.9(x-y)][0.5(x+y)-0.9(x-y)]
=(1.4x-0.4y)(-0.4x+1.4y)
=0.04(0.7x-0.2y)(0.7y-0.2x)
7、(x^2+2x)^2-(2x+4)^2
=(x^2+2x+2x+4)(x^2+2x-2x-4)
=(x+2)^2(x^2-4)
=(x+2)^2(x+2)(x-2)
=(x+2)^3(x-2)
8、a^4-16
=(a^2+4)(a^2-4)
=(a^2+4)(a+2)(a-2)
9、(x^2-2y)^2-(1-2y）^2
=(x^2-2y+1-2y)(x^2-2y-1+2y)
=(x^2-4y+1)(x^2-1)
=(x^2-4y+1)(x+1)(x-1)
10、16x^5-x
=x(16x^4-1)
=x(4x^2+1)(4x^2-1)
=x(4x^2+1)(2x+1)(2x-1)
11、3x-12x^3
=3x(1-9x^2)
=3x(1+3x)(1-3x)
12、-(a+2)^2+16(a-1)^2
=[4(a-1)+(a+2)][4(a-1)-(a+2)]
=(5a-2)(3a-6)
=3(5a-2)(a-2)
13、(a+b+c)^2-(a+b-c)^2
=(a+b+c+a+b-c)[a+b+c-(a+b-c)]
=(2a+2b)2c
=4c(a+b)