试说明:无论x,y取何值时,代数式(x3+3x2y-5xy+6y3)+(y3+2xy2+x2y-2x3)-(4x2y-x
来源:学生作业帮 编辑:作业帮 分类:数学作业 时间:2024/05/18 13:07:47
试说明:无论x,y取何值时,代数式(x3+3x2y-5xy+6y3)+(y3+2xy2+x2y-2x3)-(4x2y-x3-3x
试说明:无论x,y取何值时,代数式(x^3+3x^2y-5xy+6y^3)+(y^3+2xy^2+x^2y-2x^3)-(4x^2y-x^3-3xy^2+7y^3)的值是常数.
试说明:无论x,y取何值时,代数式(x^3+3x^2y-5xy+6y^3)+(y^3+2xy^2+x^2y-2x^3)-(4x^2y-x^3-3xy^2+7y^3)的值是常数.
(x^3+3x^2y-5xy【此处你抄错了应为:5xy^2】+6y^3)+(y^3+2xy^2+x^2y-2x^3)-(4x^2y-x^3-3xy^2+7y^3)
=x^3+3x^2y-5xy+6y^3+y^3+2xy^2+x^2y-2x^3-4x^2y+x^3+3xy^2-7y^3
=(x^3-2x^3+x^3)+(3x^2y+x^2y-4x^2y)+(-5xy^2+2xy^2+3xy^2)+(6y^3+y^3-7y^3)
=0+0+0=0
可知:代数式的值与x,y的取值无关.证毕
=x^3+3x^2y-5xy+6y^3+y^3+2xy^2+x^2y-2x^3-4x^2y+x^3+3xy^2-7y^3
=(x^3-2x^3+x^3)+(3x^2y+x^2y-4x^2y)+(-5xy^2+2xy^2+3xy^2)+(6y^3+y^3-7y^3)
=0+0+0=0
可知:代数式的值与x,y的取值无关.证毕
已知A=x3-2y3+3x2y+xy2-3xy+4,B=y3-x3-4x2y-3xy-3xy2+3,C=y3+x2y+2
有这样一道题:“计算(2x3-3x2y-2xy2)-(x3-2xy2+y3)+(-x3+3x2y-y3)的值,其中x=1
已知A=x3+3x2y-5xy2+6y3-1,B=y3+2xy2+x2y-2x3+2,C=x3-4x2y+3xy2-7y
已知x+y=10,xy=24,求x3+y3-x2y-xy2的值
因式分解:x3-y3-x2y+xy2
小明在解答题目:“已知x=3,y=-1,求代数式(x3+3x2y-5xy2+6x3+1)-(2x3-y3-2xy2-x2
当x=2011,y=2012时,求代数式3x3-4x3y2+3x2y+2x2+4x3y2+2x2y-5x2-5x2y+x
(x3-2y3-3x2y)-(3x3-3y3-7x2y)
已知﹙x+2﹚2+|y﹢1|=0,求x3+3x2y+3xy2+y3的值
已知x-y≠0 x2-x=7 y2-y=7 求x3+y3+x2y+xy2的值
已知(x+2)2+|y-1|=0,求x3(是三次方,打不出来)+3x2y+3xy2+y3(同上) 要有过程.
当x=-1,y=1时求代数式2x2y-(5xy2-3x2y)-x2的值