X-Y看成一个整数,合并多项式（X-Y)²+3(X-Y)-2(Y-X),可得?
（X-Y)²+3(X-Y)-2(Y-X),
= （X-Y)²+3(X-Y)+ 2(x-y),
= （X-Y)²+5(X-Y)
= (x-y) (x-y +5 )
施主,我看你骨骼清奇,
器宇轩昂,且有慧根,
乃是万中无一的武林奇才.
潜心修习,将来必成大器,
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