x²-xy-2y²-x+5y-2=?谢谢o(∩_∩)o
来源:学生作业帮助网 编辑:作业帮 时间:2024/07/02 01:14:44
![x²-xy-2y²-x+5y-2=?谢谢o(∩_∩)o](/uploads/image/z/2100245-5-5.jpg?t=x%26%23178%3B-xy-2y%26%23178%3B-x%2B5y-2%3D%3F%E8%B0%A2%E8%B0%A2o%28%E2%88%A9_%E2%88%A9%29o)
x²-xy-2y²-x+5y-2=?谢谢o(∩_∩)o
x²-xy-2y²-x+5y-2=?谢谢o(∩_∩)o
x²-xy-2y²-x+5y-2=?谢谢o(∩_∩)o
=(x-2y)(x+y)-x+5y-2
=(x-2y)(x+y)-2x+x+y+4y-2
=(x-2y)(x+y)+(x+y)-2x+4y-2
=(x+y)(x-2y+1)-2(x-2y+1)
=(x-2y+1)(x+y-2)
将Y看做一个常数,然后利用十字交叉法就可以得到(X-2Y)(4X+3Y)=0
就有:X=2Y,4X=-3Y,所以X/Y=2或X=-3/4
7月w5