A C B成等比数列:c*c=ab(1)
ABC等差:2b=a+c(2)
(2),得b=(a+c)/2 (3)
(3)代入(1),有(a+2c)(a-c)=0
因为a不等于c,则a=-2c (4)
(4)代入(3),有b=-c/2
则a:b:c=-4:-1:2
A C B成等比数列:c*c=ab(1)
ABC等差:2b=a+c(2)
(2),得b=(a+c)/2 (3)
(3)代入(1),有(a+2c)(a-c)=0
因为a不等于c,则a=-2c (4)
(4)代入(3),有b=-c/2
则a:b:c=-4:-1:2