- #1
TomMe
- 51
- 0
How can I calculate cos 72° and sin 72° using complex numbers, and without the use of a calculator?
I noticed that 5*72° = 360° so (cos 72° + i*sin 72°)^5 = 1. But, I don't quite know how to go from there.. :shy:
I noticed that 5*72° = 360° so (cos 72° + i*sin 72°)^5 = 1. But, I don't quite know how to go from there.. :shy: