# Tagged Questions

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Why $(1- \sin \alpha + \cos \alpha)^2 = 2 (1 - \sin \alpha)(1+ \cos \alpha)$? I am learning trigonometric identities one identity I have to proof is the next: $(1- \sin \alpha + \cos \alpha)^2 = ... 2answers 2k views ### How to simplfiy$ \cos^{2}(\theta) \sin(\theta) $to terms of$\sin$or$\cos$only? Is it possible to simplify $$\cos^{2}(\theta) \sin(\theta)$$ to terms of only$\sin$or$\cos$? I need to simplify this to take the integral. 6answers 226 views ### Help me to remember$\operatorname{cosh}^{2}(y) -\operatorname{sinh}^{2}(y)=1\$, some easy verification and deduction?

I can faintly visualize some way of deducing this formula with exponential functions but forgot it. How do you remember it? Suppose you just forget whether it is plus-or-minus there, how do you find ...
Suppose that you have to prove the trig identity: $$\frac{\sin\theta - \sin^3\theta}{\cos^2\theta}=\sin\theta$$ I have always been told that I should manipulate the left and right sides of the ...