对称三相电路的有功功率其中φ是（）。

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SQL Error: select id,body,options from ***_enewstiku where sourceid='32633' and id < 2594918 and id<>'2594918' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='32633' and id > 2594918 and id<>'2594918' order by id asc limit 5