以知1/x=3/y=5/z,求4x^2+2yz+z^2/x+y-z*x-z-y/8x^2+4yz+2z^2的值.

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以知1/x=3/y=5/z,求4x^2+2yz+z^2/x+y-z*x-z-y/8x^2+4yz+2z^2的值.以知1/x=3/y=5/z,求4x^2+2yz+z^2/x+y-z*x-z-y/8x^2

以知1/x=3/y=5/z,求4x^2+2yz+z^2/x+y-z*x-z-y/8x^2+4yz+2z^2的值.
以知1/x=3/y=5/z,求4x^2+2yz+z^2/x+y-z*x-z-y/8x^2+4yz+2z^2的值.

以知1/x=3/y=5/z,求4x^2+2yz+z^2/x+y-z*x-z-y/8x^2+4yz+2z^2的值.
4x^2+2yz+z^2/x+y-z*x-z-y/8x^2+4yz+2z^2是什么东东?最好重发一下题目否则只有按我的理解来做了.
两种方法:
1、原始方法:设1/x=3/y=5/z=1/k,则x=k,y=3k,z=5k
4x^2+2yz+z^2/x+y-z*x-z-y/8x^2+4yz+2z^2
=4k^2+2*3k*5k+(5k)^2/k+3k-5k*k-5k-3k/8k^2+4*3k*5k+2(5k)^2
=59k^2/-k*-7k/118k^2=7/2
2、特殊值法:令x=1,y=3,z=5代入上式可求(略).