[(x-y)²+(x+y)²](x²-y²)计算
问题描述：
[(x-y)²+(x+y)²](x²-y²)计算
答
原式=(x²-2xy+y²+x²+2xy+y²)(x²-y²)
=2(x²+y²)(x²-y²)
=2(x⁴-y⁴)
=2x⁴-2y⁴