方程式简化.2/(x+y)(x-y)-5/3(3-y)简化,2/和5/后面的是分母(x+y)(x-y)和(3-y)是2和5的除数。

Question

方程式简化.
2/(x+y)(x-y) - 5/3(3-y)
简化,2/ 和 5/ 后面的是分母
(x+y)(x-y) 和 (3-y) 是2和5的除数。

Answer 1

答：2/[(x+y)(x-y)]-5/[3(3-y)]=2/(x²-y²)-5/[3(3-y)]=[6(3-y)-5(x²-y²)]/[3(3-y)(x²-y²)]=(5y²-5x²-6y+18)/[3(3-y)(x²-y²)]这个不是方程式,是代数式,这样的化简...