How do I get from the primary to the secondary solution of a trigonometric equation? This book tells me that the second angle is within [itex]-\pi \leq \theta \leq \pi[/itex], in a different quadrent, but I don't follow :\(adsbygoogle = window.adsbygoogle || []).push({});

Thanks.

Edit:I got it (I think!): I can pick the correct quadrent using the sign of the ratio and knowing where each trig function is positive or negative. Then, I know (as an example) [itex]\sin \theta = +\sin \alpha[/itex], where [itex]\alpha = 180 - \theta[/itex] if we're talking about first and second quadrents.

Please correct me if I'm wrong, but I seem to be getting correct answers

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# Trig Equations

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