z分之x y=y分之x z=x分之y x=k求kx 2y=0的正整数解
来源:学生作业帮助网 编辑:作业帮 时间:2024/06/14 14:11:29
由题意可以知道:x/3=y=z/4,所以x=3y,z=4y.xy+xz+yz=76把xz都换成y可以得到:3y^2+12y^2+4y^2=76解得:y^2=4x^2=(3y)^2=36z^2=(4y)
2x-3y-z=0(1)x+3y-14z=0(2)(1)+(2)3x-15z=0x=5z(2)*2-(1)6y-28z+3y+z=09y=27zy=3z代入(4x^2-5xy+z^2)/(xy+yz+
很简单嘛代换一哈得到x=3y,z=4y,带入后面的那个得到y^2=4,x^2=36,z^2=64,所以最终答案为696,给分吧.如果错了,我就不陪读过书了!
4x-3y-3z=0(1)x-3y-z=0(2)(1)-(2)3x-2z=0z=(3/2)x(1)-(2)×34x-3y-3x+9y=0x-6y=0y=(1/6)x所以xz=x*(3/2)x=(3/2
设x/2=y/3=z/4=a则:x=2a;y=3a;z=4a代入得:(xy+yz+zx)/(x^2+y^2+z^2)=(6a^2+12a^2+8a^2)/(4a^2+9a^2+16a^2)=26a^2
"x²+y²+z²+xy+yz+xz"应该是"x²+y²+z²-xy-yz-xz"吧x-y=3/2,z-y=5/2两式相减得x-z=-1x&
∵1/x+1/y=1/6,1/y+1/z=1/9,1/z+1/x=1/15∴(1/x+1/y)+(1/y+1/z)+(1/z+1/x)=1/6+1/9+1/152(1/x+1/y+1/z)=15/90
xy/(x+y)=51/x+1/y=1/5yz/(y+z)=7/21/y+1/z=2/7zx/(z+x)=41/x+1/z=1/4(xy+yz+zx)分之xyz=1/(1/x+1/y+1/z)=280
x+y分之xy=1,y+z分之yz=2,z+x分之zx=3每个等式左右均取倒数,所以:1/x+1/y=11/y+1/z=1/21/z+1/x=1/3设:1/x=a1/y=b1/z=ca+b=1----
令3分之x=4分之y=6分之z=kx=3k,y=4kz=6k(xy+yz+xz)/(x^2+y^2+z^2)=k^2(12+18+24)/k^2(36+16+9)=54/61
可知:x=3yz=4y代入得:3y^2+12y^2+4y^2=76y^2=4x^2=36z^2=64得答案:696
已知(xy分之x+y)的-1次方=1,则xy=x+yy=x/(x-1)(yz分之y+z)的-1次方=2,则yz=2y+2zz=2y/(y-2)(xz分之x+z)的-1次方=3,则xz=3x+3zz=3
设z/(x+y)=y/(x+z)=x/(y+z)=1/k,则:z=1/k(x+y)(1)y=1/k(x+z)(2)x=1/k(y+z)(3)(1)+(2)+(3)得:x+y+z=2*(1/k)(x+y
设x/3=y/2=z/4=kx=3k,y=2k,z=4k(xy+yz+xz)/(x^2+y^2+z^2)=(6+8+12)/(9+4+16)=26/29
答案是11分之14. 求采纳
4x-3y-6z=0,(1)x+2y-7z=0,(2)(2)×4-(1)得:11y=22zy=2z代入(2)得:x=7z-4zx=3zxy+2yz+xz分之2x^2+3y^2+6z^2=(18z
令3/x=4/y=6/z=1/k则x=3ky=4kz=6k(x²+y²+z²)/(xy+yz+xz)=(9k²+16k²+36k²)/(12
2x-3y-z=0,x+3y-14z=0两式相加可得x=5z2式乘以2减去1式可得y=9z用上式把xy+yz+xz分之4x²-5xy+z²中x,y代替掉可得答案
1/x+1/y=3(1)1/y+1/z=2(2)1/x+1/z=1(3)(1)+(2)+(3)2(1/x+1/y+1/z)=61/x+1/y+1/z=3(4)由(1)1/z=0题目有误,请核对,或者更