分式的基本性质 3x=2y=5z不等于0 求x-y z分之x 2y 3z-搜答案-搜搜做题作业网

原式=-3xy*3x/2y²=-9x²/2y

x\2=y\3=z\5=kx=2ky=3kz=5k2x+3y–z\3x-2y+z=(4k+9k-5k)\(6k-6k+5k)=8/5

设z=a则x=4a,y=3a(2x-3y+5z)/(x+y+z)=(8a-9a+5a)/(a+4a+3a)=0.5

设X/2=y/3=z/4=kx=2k,y=3k,z=4kx+y-z/x+y+z=2k+3k-4k/2k+3k+4k=k/9k=1/9

三分之X=四分之Y=五分之Zx：y：z=3:4:5设x=3ay=4az=5a(x+y)/(x-2y+3z)=(3a+4a)/(3a-8a+15a)=7a/10a=7/10

(x+y)/z=(x+z)/y=(z+y)/xx,y,z等价x=y=z(x+y)(x+z)(z+x)/xyz=8

1/x-1/y=(y-x)/xy=1y-x=xy(3y-xy-3x)/(x-xy-y)=(3y-y+x-3x)/(x-y+x-y)(2y-2x)/(2x-2y)=-1

x^2-y^2/(x+y)^2=x-y/(x+y)再问：能说明理由么？x^2-y^2和(x+y)^2是不一样的再答：分子分解因式得(x+y)(x-y)x+y≠0分式分子分母同除以一个不为0的整式，分式

y-x=3xyx-y=-3xyx-2xy-y=-5xy2x+3xy-2y=2(x+y)+3xy=-6xy+3xy=-3xy分式x-2xy-y分之2x+3xy-2y=5/3

分式的基本性质2

解题思路：分式的通分与应用解题过程：varSWOC={};SWOC.tip=false;try{SWOCX2.OpenFile("http://dayi.prcedu.com/include/read

由题意得｛x+y+z=02x-y-7z=0=｛x+z=-yβ2x-7z=ypβ+p得x=2z,把x=2z带入β=-3z当x=2z,β=-3z时原式=【3×2z×（-3z）-（4z）²】除以（

设x/4=y/3=z/2=k【k不等于0】则x=4k,y=3k,z=2k把x、y、z的值代入原式中得到（4k）方+（3k）方/(12k方-8k方）化简得25k方/4k方,k方约分掉,可得到25/4【2

(x+4)分之（-x-5)

令x=2a,y=3a,z=4a,于是x-y-z/2x+3y=(-5a)/(13a)=-5/13

x^2-xy/2x-2y=x(x-y)/2(x-y)=x/2∴括号里应该填2很高兴为您解答,祝你学习进步!【学习宝典】团队为您答题.有不明白的可以追问!如果您认可我的回答.请点击下面的【选为满意回答】

在这两个比中都有相同的数x,所以要把x通分,3和4的最小公倍数是12.所以x比y=3比7=12比28,x比z=4比1=12比3,y比z=28比3

设x/2=y/3=z/-1=ax=2ay=3az=-a(2x+6y-3z)/(x+y+2z)=(4a+18a+3a)/(3a)=25a/3a=25/3

x/3=y/2=z/5=tx=3ty=2tz=5t∴(xy+yz+zx)/(x的平方+y的平方+z的平方)=(6t²+10t²+15t²)/(9t²+4t

x=4/5yz=4/5yx+2y-3z/2x-3y=(4/5y+2y-12/5y)/(8/5y-3y)=(2/5y)/(-7/5y)=-(2/7)