若i=+i2，i=10sinwtA，i=10sin（2wt+90°）A，则i的有效值为（）。

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SQL Error: select id,body,options from ***_enewstiku where sourceid='32677' and id < 2599479 and id<>'2599479' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='32677' and id > 2599479 and id<>'2599479' order by id asc limit 5