1/3a=1/4b=1/5c 3a=4b=5c a:b:c
已知正数a、b、c满足3a+4b+5c=1,求1/(a+b)+1/(b+c)+1/(c+a)的最小值.
已知正数a、b、c满足3a+4b+5c=1,求1/(a+b)+1/(b+c)+1/(c+a)的最小值
b/(a+c)=1/2,a/(b+c)=1/5 怎么得出a/(a+b+c)=1/6,b/(a+b+c)=1/3?
1/3a=1/4b=1/5c 3a=4b=5c a:b:c
1、3a+2b-5/a-b+2=2b+c+1/3b+2c-8=c-3a+2/2c+a-6=2,求a+2b+3c-2/4a
若|a|=3|b|=1|c|=5且|a+b|=a+b,|a+c|=-(a+c)求a+b+c的值
设a=3,b=4,c=5试计算以下表达式:(1)a=b>c&&b==c (2)a||b+c&&b-c (3)(!(a+b
解方程 1,a+b+c=6 3a-2b+4c=11 2a-3b+2c=2 2,a:b:c=3:4:5 a+b+c=36
a+b+c=9,a+b-c=1,a-b+c=3,a,b,c多少 -
设a,b,c是实数,3a,4b,5c成等比数列,且1/a,1/b,1/c成等比数列,求a/c+c/a
若c不等于0,3a=5b+2c,3/2a+1/2b=4c.求a:b:c.
A=B+B+B+B+B+B+B+B+B+B+B+B+B+B+B A-B×3=C C+2×7+2=1