Hi im kind of new to assembly and im starting to get familiar with ARM assembly combined with the NEON coprocessor in some of the new ARM chips. One of the things I am not sure how to do is high level math functions like sin,cos,tan,exp,etc.. If I disassemble C code that has these math functions it seems that they are external.
The best option for you seems like it would be to simply link the other libraries in your assembly project. I don't see any reason to recreate the wheel if all you want the exact same functionality.
If this is a learning process then I suggest you either start with something simpler, as it doesn't sound like you have the experience to tackle a problem like this, or look into the higher-degree polynomials that user786653 suggested.