两个正弦电流：i1=15sin（100πt+45°），i2=15sin（200πt-30°），以下说法正确的是（）_电工基础知识_全学科试题题库

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两个正弦电流：i1=15sin（100πt+45°），i2=15sin（200πt-30°），以下说法正确的是（）
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