(5分)记$S_{n}$为等差数列$\{a_{n}\}$的前$n$项和.若$2S_{3}=3S_{2}+6$,则公差$d=$ 2 . 分析:根据已知条件,可得$2(a_{1}+a_{2}+a_{3})=3(a_{1}+a_{2})+6$,再结合等差中项的性质,即可求解. 解:$\because 2S_{3}=3S_{2}+6$, $\therefore 2(a_{1}+a_{2}+a_{3})=3(a_{1}+a_{2})+6$, $\because \{a_{n}\}$为等差数列, $\therefore 6a_{2}=3a_{1}+3a_{2}+6$, $\therefore 3(a_{2}-a_{1})=3d=6$,解得$d=2$. 故答案为:2. 点评:本题主要考查等差数列的前$n$项和,考查转化能力,属于基础题.
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