I can't get anywhere with these three identities. Any tips?(adsbygoogle = window.adsbygoogle || []).push({});

[tex]\frac{(\sec \theta - \tan \theta)^2 + 1}{\csc \theta(\sec \theta - \tan \theta)} = 2 \tan \theta[/tex]

[tex]\frac{\sin^3 \theta + \cos^3 \theta}{\sin \theta + \cos \theta} = 1 - \sin \theta\cos \theta[/tex]

[tex](2a\sin \theta\cos \theta)^2 + a^2(\cos^2 \theta - \sin^2 \theta)^2 = a^2[/tex]

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# Homework Help: Trig Identities

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