# Is it just a coincidence or is it related to how values of sine calculated?

Actually, one of my math teacher told me about this. I want to know is there any relationship between this trick and their respective values?

• Sin and cos mirror eachother because they are co-functions. One value depends on the other due to $sin^2(x) + cos^2(x) = 1$. As for the values themselves, there is no relation. It just so happens a trick could be made for those 5 values. – Kaynex Dec 24 '15 at 21:44
• This question shows patterns for some other sets of angles. – Blue Dec 24 '15 at 22:11
• The Math Forum shows how to derive those angles. – cr3 Dec 24 '15 at 23:24