已知x/2=y/3=z/4,求(xy+yz+zx)/x²+y²+z²的值
问题描述:
已知x/2=y/3=z/4,求(xy+yz+zx)/x²+y²+z²的值
答
x/2=y/3=z/4=m,则x=2m,y=3m,z=4m.原式=(6m²+12m²+8m²)/(4m²+9m²+16m²)=26/29
已知x/2=y/3=z/4,求(xy+yz+zx)/x²+y²+z²的值
x/2=y/3=z/4=m,则x=2m,y=3m,z=4m.原式=(6m²+12m²+8m²)/(4m²+9m²+16m²)=26/29