1、原式=3(x^2-4)/(x-2)^2=3(x+2)/(x-2)
2、原式=x(x-3)/-(x-3)^2=x/-(x-3)=x/(3-x)
3、原式=a^2-4ab+4b^2/a^2-4b^2=(a-2b)^2/(a-2b)(a+2b)=a-2b/a+2b
4、原式=2(2b-5a)/(5a-2b)^2=2/2b-5a
1、原式=3(x^2-4)/(x-2)^2=3(x+2)/(x-2)
2、原式=x(x-3)/-(x-3)^2=x/-(x-3)=x/(3-x)
3、原式=a^2-4ab+4b^2/a^2-4b^2=(a-2b)^2/(a-2b)(a+2b)=a-2b/a+2b
4、原式=2(2b-5a)/(5a-2b)^2=2/2b-5a