(x+y)(x²-xy+y²)等于几啊

来源：学生作业帮编辑：作业帮分类：数学作业时间：2024/05/25 10:11:34

(x+y)(x²-xy+y²)等于几啊

原式=x³+y³
这是立方和公式
再问：谢谢但是有过程吗
再答： (x+y)(x²-xy+y²) =x(x²-xy+y²)+y(x²-xy+y²) =x³-x²y+xy²+x²y-xy²+y³ =x³+(-1+1)x²y+(1-1)xy²+y³ =x³+y³

xy+x-y=18,x,y各等于几 x²/xy-x/y 若2x²—4x+2+根号x+2y—1等于0,那么xy等于几? 计算：(xy-x²)×x-y/xy 2x(x²y-xy²)+xy(xy-x²)]÷x²y等于多少 3xy+xy+2x²y+yx²+3x²y等于多少 3y/2x+2y + 2xy/x²+xy等于多少过程已知x/y等于3,求x²+2xy-3y²/x²-xy+y²的值 (x+2y-1)²等于几? [-xy/(x-y)²]²×(y²-xy/x)³ x/xy-y²与y/x²-xy 通分 |x+y-4|+(xy-5)²等于0,则x²+y²等于?