无论x,y取何值时,代数式:(x³+3x²y-5xy+6y³)+(y³+2xy²+x²y-2x³)-(4x²y-x³-3xy²+7y³)的值是常熟.
来源:学生作业帮助网 编辑:作业帮 时间:2024/06/22 03:24:24
![无论x,y取何值时,代数式:(x³+3x²y-5xy+6y³)+(y³+2xy²+x²y-2x³)-(4x²y-x³-3xy²+7y³)的值是常熟.](/uploads/image/z/12974151-39-1.jpg?t=%E6%97%A0%E8%AE%BAx%2Cy%E5%8F%96%E4%BD%95%E5%80%BC%E6%97%B6%2C%E4%BB%A3%E6%95%B0%E5%BC%8F%EF%BC%9A%EF%BC%88x%26%23179%3B%2B3x%26%23178%3By-5xy%2B6y%26%23179%3B%EF%BC%89%2B%EF%BC%88y%26%23179%3B%2B2xy%26%23178%3B%2Bx%26%23178%3By-2x%26%23179%3B%EF%BC%89-%EF%BC%884x%26%23178%3By-x%26%23179%3B-3xy%26%23178%3B%2B7y%26%23179%3B%EF%BC%89%E7%9A%84%E5%80%BC%E6%98%AF%E5%B8%B8%E7%86%9F.)
无论x,y取何值时,代数式:(x³+3x²y-5xy+6y³)+(y³+2xy²+x²y-2x³)-(4x²y-x³-3xy²+7y³)的值是常熟.
无论x,y取何值时,代数式:(x³+3x²y-5xy+6y³)+(y³+2xy²+x²y-2x³)-(4x²y-x³-3xy²+7y³)的值是常熟.
无论x,y取何值时,代数式:(x³+3x²y-5xy+6y³)+(y³+2xy²+x²y-2x³)-(4x²y-x³-3xy²+7y³)的值是常熟.
∵
(x³+3x²y-5xy+6y³)+(y³+2xy²+x²y-2x³)-(4x²y-x³-3xy²+7y³)
=x³+3x²y-5xy²+6y³+y³+2xy²+x²y-2x³-4x²y+x³+3xy²-7y³
=0
∴无论x,y取何值时,代数式:(x³+3x²y-5xy+6y³)+(y³+2xy²+x²y-2x³)-(4x²y-x³-3xy²+7y³)的值是常数.