I have a question that says an equivalent expression for [tex]\cos\frac {3\theta} {2} \cos \frac {\theta} {2} + \sin \frac {3\theta} {2} \sin\frac {\theta} {2} [/tex] is??(adsbygoogle = window.adsbygoogle || []).push({});

How do u get the answer to be [tex] \cos \theta [/tex]?

Can someone please help me out?

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# Homework Help: Help with math expression

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