x的平方-2x除以2y-xy,其中x等于-6
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因为正数x,y满足x平方-y平方=2xy,所以(x^2-y^2)=2xy即1-(y/x)^2=2(y/x)(y/x)^2+2(y/x)-1=0y/x=[-2+√(4+4)]/2=-1+√2(因为x,y
1-(x-y)/(x+2y)÷(x²-y²)/(x+2y)²=1-(x-y)/(x+2y)×(x+2y)²/(x+y)(x-y)=1-(x+2y)/(x+y)=
原式=[x²-4xy+﹙2y﹚²-1]/﹙x-2y-1﹚=[﹙x-2y﹚²-1²]/﹙x-2y-1﹚=﹙x-2y+1﹚﹙x-2y-1﹚/﹙x-2y-1﹚=x-2
3x^2+xy-2y^2=(3x-2y)(x+y)=0x=-2y/3,或x=-y但由于你要求的式子中分母里有X平方-Y平方x=-y舍去其他就代入吧
解题有点难写,你找我上Q吧,我语聊告诉你,1256769059
1、原式=[2x/(x^2-1)]-[(x+1)/(x^2-1)]=[2x-(x+1)]/(x^2-1)=(x-1)/(x^2-1)=(x-1)/[(x+1)(x-1)]=1/(x+1)2、原式=[x
(xy-x的平方)除以xy分之x的平方-2xy+y的平方乘x的平方分之x-y=x(y-x)*xy/(x-y)²*(x-y)/x²=-y再问:不好意思,打错了(xy-y的平方)除以x
^2代表平方,/代表分数线和除号由题意得设x=3k,y=2k(k不等于0)代入原式=(9k^2+18k^2)/(6k^2+8k^2)=27k^2/14k^2=27/14所以原式的值为14分之27.
【x的平方-2x】除以2y-xy=x(x-2)/[-y(x-2)]=-x/y
x的平方+3xy+2y的平方除以x的平方y+2xy的平方=(x+2y)(x+y)/xy(x+2y)=12/9=4/3再问:那个再问一下不改变分式的值使分式的分子分母首项系数都是正数-(负7xy/负8z
=(xy-x的平方)除以(x的平方-2xy+y的平方\xy)乘以(x-y\x的平方)=-x(x-y)×xy/(x-y)2×(x-y)/x2=-y再问:嗯
(xy-x²)÷(x²-2xy+y²)./xy·(x-y)/x²=-x(x-y)·xy/(x-y)²·(x-y)/x²=-x²y(
x平方+y平方+2xy分之x平方-4y平方除以x平方+xy分之2y+x=(x-2y)(x+2y)/(x+y)²·x(x+y)/(x+2y)=x(x-2y)/(x+y)
=(xy-x的平方)除以(x的平方-2xy+y的平方\xy)乘以(x-y\x的平方)=-x(x-y)×xy/(x-y)²×(x-y)/x²=-y
(3x^2-xy)/(3x^2+5xy-2y^2)=x(3x-y)/[(3x-y)(x+2y)]=x/(x+2y)
x(y-x)÷(x²-2xy+y²)/xy×(x-y)/x²=-x(x-y)×xy/(x-y)²×(x-y)/x²=-y
(x²+xy)/(x+y)²=x(x+y)/(x+y)²=x/(x+y)2xy/(x+y)²x/(x²-y²)∵最简公分母为:(x+y)
因式分解原式=[x(x-2)]/[-y(x-2)]=-x/y
(x+y)分之(x²-y²)×(x²+xy)分之(2x+2y)÷(x-y)=(x+y)分之[(x+y)(x-y)]×[x(x+y)]分之[2(x+y)]×(x-y)分之1