((2x²+y﹚²-5y²(3x²+1)-4(x²+y)(x²-y))÷5x²y

问题描述:

((2x²+y﹚²-5y²(3x²+1)-4(x²+y)(x²-y))÷5x²y

((2x²+y﹚²-5y²(3x²+1)-4(x²+y)(x²-y))÷5x²y
=(4x^4+4x²y+y²-15x²y²-15y²-4(x^4-y²))÷5x²y
=(4x^4+4x²y+y²-15x²y²-15y²-4x^4+4y²))÷5x²y
=(4x²y-15x²y²-10y²)÷5x²y
=4/5 - 3y -2y/x²其中x=99,y=2/15刚才有点问题,应该是 ((2x²+y﹚²-5y²(3x²+1)-4(x²+y)(x²-y))÷5x²y =(4x^4+4x²y+y²-15x²y²-5y²-4(x^4-y²))÷5x²y =(4x^4+4x²y+y²-15x²y²-5y²-4x^4+4y²))÷5x²y =(4x²y-15x²y²)÷5x²y =4/5 - 3y=4/5 - 2/5 =2/5刚才应该是对的把2/5肯定是对的最上面的那个稍微有点问题 应该是-5y² 而不是-15y²