
Re: probably need to go to a 3rd power polynomial
Posted:
Feb 20, 2017 2:59 AM


On Sun, 19 Feb 2017 22:42:59 0800 (PST), Archimedes Plutonium wrote:
>Alright, at bare minimum I need to get this table: > >x y >0 0 >.5 .86 >1 1 >1.5 .86 >2 0 > >Now I can come reasonably close by .1 or less, but if more than .1, the game is off > >So far, the best two equations for sine and cosine are these two > >.4x^2 + 1.6x + .09 > >.6x^2  .3x +1 > >Troubles: the first gives 0 as .09, then gives .8 which is good, but gives 1.3 when I need 1. The second gives 1 at 0, good, then .7 when I need .86, then .1 when I need 0 which is acceptable. So unless I can mend the two to fit better, then I must go to a 3rd power polynomial. > >AP
Actually, the best two equations for sine and cosine are these two: y = sin(x) y = cos(x)

