1、（3a²分之2）+（4b分之3）-（6ab分之5）
=8b/12a^2b+9a^2/12a^2b-10a/12a^2b
=(8b+9a^2-10a)/12a^2b
2、（x²-x分之1）+（2x²-2分之x-5）
=2(x+1)/2x(x+1)(x-1)+x(x-5)/2x(x+1)(x-1)
=(2x+2+x^2-5x(/2x(x+1)(x-1)
=(x-1)(x-2)/2x(x+1)(x-1)
=(x-2)(2x^2+2x)
3、（x-y分之x）+x（y-x）分之y²
=x^2/x(x-y)-y^2/x(x-y)
=(x^2-y^2)/x(x-y)
=(x+y)(x-y)/x(x-y)
=(x+y)/x
4、（2a+2b分之a(chǎn)-b）- a²-b²分之a(chǎn)²+b²
=(a-b)^2/2(a+b)(a-b)-2(a^2+b^2)/2(a+b)(a-b)
=(a^2-2ab+b^2-2a^2-2b^2)/2(a+b)(a-b)
=-(a+b)^2/2(a+b)(a-b)
=-(a+b)/(2a-2b)