化简(x²+y²)(x²-y²)-(x+y)²(x-y)²
问题描述：
化简(x²+y²)(x²-y²)-(x+y)²(x-y)²
化简求值 x=4 y=1
答
(x²+y²)(x²-y²)-(x+y)²(x-y)²=[(x²)²-(y²)²]-[(x+y)(x-y)]²=(x^4-y^4)-(x²-y²)²=(x^4-y^4)-(x^4-2x²y²+y^4)=2x²y²-2y^...化简求值 x=4y=1最后结果是30么？代入：2y²(x-y)(x+y)=2×1²×(4-1)×(4+1)=2×1×3×5=30结果是30