HP-35 style trig functions

[Druzyek]

I've been looking at HP-35 CORDIC routines for calculating tangent using decimal numbers (here and here) so I can use them for a calculator I'm building. The site shows that once you find tangent, you can use square root and multiplies to find sine and cosine. Is there another algorithm you can use to find just sine or just cosine that doesn't require square root and multiply? Unlike the HP-35 designers, I have plenty of space for extra algorithms and tables I did try implementing the standard powers of 2 CORDIC, but since I'm working with BCD numbers, it turned out extremely slow.