Hey. The latest thing we've been studying in trig classes is equations of the form:(adsbygoogle = window.adsbygoogle || []).push({});

[tex]

a\cos \theta + b\sin \theta = c

[/tex]

The book explains that to solve an equation like this, i should write it in the form:

[tex]

a\cos \theta + b\sin \theta = \sqrt {a^2 + b^2 } \cos (\theta - \alpha )

[/tex]

Now. The teacher has tried all she can to explain how the second form can be derived, but nobody seems to understand. Could someone please go through it?

Thanks,

Dan.

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# Homework Help: Trig equations in the form

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