当X=-1,Y=-2时,代数式X的Y的平方等于
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x+y/x-y=1/2取倒数x-y/x+y=2所以x-y/x+y-2x+2y/x-y=x-y/x+y-2(x+y/x-y)=2-2×1/2=2-1=1
(x+1)的平方+y-2的绝对值=0x+1=0x=-1y-2=0y=2x-y/xy=(-1-2)/(-2)=3/2再问:那个y为什莫事2?
3x^2y-xy^2=xy(3x-y)将x=-1/2y=1代入有-1/2*1*[3*(-1/2)-1]=-1/2*(-5/2)=5/4
因为:当x=2时,px^3+qx+1=2002所以:8p^3+2q=2001.(1)当x=-2时,px^3+qx+1=-8p^3-2q+1=-(8p^3+2q)+1将(1)代入,得:-2001+1=-
k=8/3再答:3分之8再答:再答:我的回答满意吗?望采纳再问:再答:估计是老师看错了
|y-x|-2|xy|=|-3-(-2)|-2|-2×(-3)|=|-1|-2|6|=1-2×6=1-12=11很高兴为您解答,【学习宝典】团队为您答题.请点击下面的【选为满意回答】按钮,
原式=1/2×2x-y/x+y+2x-y/6x-3y=1/2+1/3=5/6
当x=1时,y=2代入2=a+b+c……(1)当x=-1时,y=-2代入-2=a-b+c……(2)当x=2时,y=33=4a+2b+c……(3)由(1)(2)(3)得出a=-1/3b=2c=1/3当x
x^4-xy^3-x^3y-3x^2y+3xy^2+y^4=x^4-x^3y-3xy(x-y)+y^4-xy^3=x^3(x-y)-3xy(x-y)-y^3(x-y)=(x-y)(x^3-3xy-y^
原试=-y-y-y.-y大概有50个-y所以答案是-50/3
哦,等等我看看再问:恩再答:再问:已知方程组x+y=t+1x-y=2t-1中,已知y>8,求x的取值范围再问:这题怎么写再答:虽然你已经给了财富,我还是帮你在想想吧!等我一会。再答:抱歉,题目我写错了
(3x+2y)(3x-2y)-(x-y)^2=(9x^2-4y^2)-(x^2-2xy+y^2)=8x^2+2xy-5y^2=8+2-1.25=8.75
1、=(120-2)(120+2)=120²-2²=14400-4=143962、=2012²-(2012+1)(2012-1)=2012²-2012²
(1)把x=2,y=一4代入代数式ax3+12by+5=1997得:4a-b=996.把x=−4,y=−12代入代数式3ax-24by3+4986得:-3(4a-b)+4986.∴代数式3ax-24b
=(x-(x+y))+((x+2y)-(x+3y))+...+((x+98y)-(x+99y))=-y*50=2*50=100
根据题意得,a+b=−6①2a+3b=3②,①×2得,2a+2b=-12③,②-③得,b=15,把b=15代入①得,a+15=-6,解得a=-21,所以,代数式为-21x+15y,当x=−1y=1时,
原式=(x-y)/x/((x^2-2xy+y^2)/x)=(x-y)/x乘以(x/(x^2-2xy+y^2))=(x-y)/x乘以(x/(x-y)^2)=1/(x-y)当x=2008,y=2009原式
(x+y)(x-y)+(x-y)²-(x²-3xy)=x²-y²+x²-2xy+y²-x²+3xy=x²+xy=x(x+