作业帮急![(3x+y)²-3(3x-y)(x+y)-(x-3y)(x+3y)]÷(2xy)[(3x+y)²-3(3x-y)(x+y)-(x-3y)(x+3y)]÷(2xy)其中x=½,y=-2
来源：学生作业帮助网 编辑：作业帮 时间：2024/05/03 17:52:24
![急![(3x+y)²-3(3x-y)(x+y)-(x-3y)(x+3y)]÷(2xy)[(3x+y)²-3(3x-y)(x+y)-(x-3y)(x+3y)]÷(2xy)其中x=½,y=-2](/uploads/image/z/810751-31-1.jpg?t=%E6%80%A5%21%5B%283x%2By%29%26%23178%3B-3%283x-y%29%28x%2By%29-%28x-3y%29%28x%2B3y%29%5D%C3%B7%282xy%29%5B%283x%2By%29%26%23178%3B-3%283x-y%29%28x%2By%29-%28x-3y%29%28x%2B3y%29%5D%C3%B7%282xy%29%E5%85%B6%E4%B8%ADx%3D%26%23189%3B%2Cy%3D-2)
急![(3x+y)²-3(3x-y)(x+y)-(x-3y)(x+3y)]÷(2xy)[(3x+y)²-3(3x-y)(x+y)-(x-3y)(x+3y)]÷(2xy)其中x=½,y=-2
急![(3x+y)²-3(3x-y)(x+y)-(x-3y)(x+3y)]÷(2xy)
[(3x+y)²-3(3x-y)(x+y)-(x-3y)(x+3y)]÷(2xy)其中x=½,y=-2
急![(3x+y)²-3(3x-y)(x+y)-(x-3y)(x+3y)]÷(2xy)[(3x+y)²-3(3x-y)(x+y)-(x-3y)(x+3y)]÷(2xy)其中x=½,y=-2
原式=（9x²+6xy+y²-9x²-6xy+3y²-x²+9y²)÷2xy
=13y²÷2xy
=13y/2x
当x=1/2,y=-2时
原式=13乘以-2/2乘以1/2
=-26