已知x/3=y/1=z/2.求2x^2-2y^2+5z^2/xy+yz+zx的值
来源:学生作业帮助网 编辑:作业帮 时间:2024/09/02 01:36:25
![已知x/3=y/1=z/2.求2x^2-2y^2+5z^2/xy+yz+zx的值](/uploads/image/z/1240723-19-3.jpg?t=%E5%B7%B2%E7%9F%A5x%2F3%3Dy%2F1%3Dz%2F2.%E6%B1%822x%5E2-2y%5E2%2B5z%5E2%2Fxy%2Byz%2Bzx%E7%9A%84%E5%80%BC)
x10E&*^Q VK%Ʉ`a ǡ4XX,g[|*w8v5;2!X'ޖM<]3jh'aߛ"`ͮ12EQp(8C@9 HB|DrT**"Su &̧4<{p
已知x/3=y/1=z/2.求2x^2-2y^2+5z^2/xy+yz+zx的值
已知x/3=y/1=z/2.求2x^2-2y^2+5z^2/xy+yz+zx的值
已知x/3=y/1=z/2.求2x^2-2y^2+5z^2/xy+yz+zx的值
令x/3=y/1=z/2=k
x=3k,y=k,z=2k
(2x^2-2y^2+5z^2)/(xy+yz+zx)
=[2(3k)^2-2k^2+5(2k)^2]/(3k*k+k*2k+3k*2k)
=[2*9k^2-2k^2+5*4k^2]/(3k^2+2k^2+6k^2)
=[18k^2-2k^2+20k^2]/(3k^2+2k^2+6k^2)
=(36k^2)/(11k^2)
=36/11
已知实数x y z满足x/(x+1)=y/(y+2)=z/(z+3)=(x+y+z)/3,求x+y+z的值
已知实数x y z满足x/(x+1)=y/(y+2)=z/(z+3)=(x+y+z)/3,求x+y+z的值
已知(x+y)(x+z)=x,(y+z)(y+x)=2y,(z+x)(z+y)=3z,求x,y,z
已知X:Y=0.3:1/2,Y:Z=2:3,求X:Y:Z
已知(1)X-Y+Z=0 (2)X+2Y-3Z=0 求X:Y:Z
已知x:y:z=1:3:5,求(2x+3y-z)/(x+y-2z)的值
已知{x:y:z=1:2:3,x+y+z=12,求x、y、z的值
已知{2x-y-z=0,3x-9y+z=0求1,x:y:z
已知x:y:z=1:2:3,x+y+z=24,求x,y,z
已知x::y:z=3:4:5,(1)求x+y分之z的值;(2)若x+y+z=6,求x,y,z.
1、已知x/y=7/2,求x/x+y 2、已知x/2=y/3=z/4,求x+y+z/2x+3y-z!1、已知x/y=7/2,求x/x+y2、已知x/2=y/3=z/4,求x+y+z/2x+3y-z!
已知x/2=y/3=z/4,求下列各式 (1)(x+y+z)/x (2)(x-y+2x/(x-y-2z)
已知实数x,y,z满足x+y+z=2根号x-1+2根号y-1+2根号z-1求X+2Y+3Z
已知实数xyz满足x/(x+1)=y/(y+2)=z/(z+3)=(x+y+z)/3求x+y+z的值
已知正数x,y,z满足x+2y+3z=1,求最小值
已知:x^2/(z+y)+y^2/(x+z)+z^2/(x+y)=0,求x/(z+y)+y/(x+z)+z/(x+y)的值.
已知方程组【X:Y:Z=1:3:2,X+Y+Z=8】求Y+3Z的值
已知方程组x:y:z=1:3:2 x+y+z=8 求y+3z的值