问题补充：
当X=1984,Y=1916时,计算:(X的四次方-Y的四次方/X的二次方-2XY=Y的二次方)×(Y-X/X当X=1984，Y=1916时，计算：(X的四次方-Y的四次方/X的二次方-2XY=Y的二次方)×(Y-X/X的二次方+Y的二次方)=?
答案：
(X^4-Y^4)/(X²-2XY+Y²) × (Y-X)/(X²+Y²)
=(X²+Y²)(X²-Y²)/(X-Y)² × (Y-X)/(X²+Y²)
=(X²+Y²)(X-Y)(X+Y)/(X-Y)² × [-(X-Y)/(X²+Y²)]
=(X+Y)/(X-Y) × [-(X-Y)]
=-X-Y=-1984-1916
=-3900
======以下答案可供参考======
供参考答案1:
={[(x^2+y^2)(x+y)(x-y)]/(x-y)^2}*[(y-x)/(x^2+y^2)]
约分，＝[(x+y)/(x-y)]*[-(x-y)]
约分，＝-(x+y)
=-(1984+1916)
=-3900
