# Tag Info

You can use the double angle formulas (together with the small angle approximations $\sin(\theta) \approx \theta$ and $\cos(\theta) \approx 1$) to approximate sine and cosine of any number $x$ by using the small angle approximations for $\frac{x}{2^n}$ and doubling until you get $x$. This is a pretty cool "proto-calculus" way to compute sine and ...