2分之x等于3分之y等于4分之z不等于0.求3x+2y-z分之x-y-z的值
问题描述:
2分之x等于3分之y等于4分之z不等于0.求3x+2y-z分之x-y-z的值
答
3x+2y-z分之x-y-z= -5/8
2,3,4的最小公倍数是12。所以,12分之6X=12分之4Y=12分之3Z,也就是6X=4Y=3Z.
6,4,3的最小公倍数也是12,所以6X=4Y=3Z也等于6*2=4*3=3*4=12,所以X=2,Y=3,Z=4.
请验证是否对。
答
设x/2=y/3=z/4=k
则x=2k y=3k z=4k
3x+2y-z分之x-y-z
=(x-y-z)/(3x+2y-z)
=(2k-3k-4k)/(3*2k+2*3k-4k)
=(-5k)/(8k)
=-5/8
=-0.625
答
设x/2=y/3=z/4=k
则x=2k y=3k z=4k
3x+2y-z分之x-y-z
=(x-y-z)/(3x+2y-z)
=(2k-3k-4k)/(3*2k+2*3k-4k)
=(-5k)/(8k)
=-5/8 呵呵.我也在做这道题.
答
x/2=y/3=z/4
则:x=(2/3)y,z=(4/3)y
代入为:[(2/3)y-y-(4/3)y]/[3*(2/3)y+2y-(4/3)y]
=(2/3-1-4/3)/(2+2-4/3)
=-5/8