（2x+1）的平方+4（2x+1）+3=0(2x+1 +3 ) ( 2x+1 +1 ) = 0 (2x +4 ) (2x+2) = 0 4 (x +2 ) (x+1 ) = 0 x = -2 或者 x = -1 施主,我看你骨骼清奇,器宇轩昂,且有慧根,乃是万中无一的武林奇才.潜心修习,将来必成大器,鄙...