偶函数y＝f(x)满足条件f(x＋1)＝f(x－1)，且当x∈[－1,0]时，f(x)＝3 x＋ ，则f( )的值等于(　 　)

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SQL Error: select id,body,options from ***_enewstiku_ where sourceid='16551' and id < 1390159 and id<>'1390159' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku_ where sourceid='16551' and id > 1390159 and id<>'1390159' order by id asc limit 5