已知：x/2=y/3=z/4,求xy+2yz-3xz/x2+y2+z2的值

已知：x/2=y/3=z/4,求xy+2yz-3xz/x2+y2+z2的值
已知：x/2=y/3=z/4,求xy+2yz-3xz/x2+y2+z2的值

已知：x/2=y/3=z/4,求xy+2yz-3xz/x2+y2+z2的值
令x/2=y/3=z/4=k
x=2k,y=3k,z=4k
xy+2yz-3xz/x2+y2+z2
=6k²+24k²-24k²/4k²+9k²+16k²
=6k²/29k²
=6/29