## Proofs

If you have a theorem which you would like a proof of to be featured in this bank, please email it to me using the contact form.

$e^{ix}=\cos x + i\sin x$

$\frac{d}{dx}\left(\frac{u}{v}\right)=\frac{v \frac{du}{dx}-u \frac{dv}{dx}}{v^2}$ $\frac{d}{dx}(uv)=u \frac{dv}{dx}+v \frac{du}{dx}$ where u and v are functions of x.

$$\frac{d}{dx} \sin x = \cos x$$ when x is in radians