(1)若2分之A=4分之B=5分之C,求(2a+3b-5c)分之a+b+c
问题描述:
(1)若2分之A=4分之B=5分之C,求(2a+3b-5c)分之a+b+c
答
令X=A/2=B/4=C/5
A=2X,B=4X
,C=5X
(A+B+C)/(2A+3B-5C)
=(2X+4X+5X)/(4X+12X-25X)
=11X/(-9X)
=-11/9