here is a screenshot from one of my lectures talking about how to find active power (P) and reactive power (Q)(adsbygoogle = window.adsbygoogle || []).push({});

He calculates P using 100*10 Cos (30-(-30), which I understand, though the answer he gets is 200W, but whenever I calculate it I get 500 because cos60 = 0.5 and 0.5*1000 is 500.

Just wanting to know what I'm doing wrong.

Thanks.

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# Possible lecture error

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