Date: Feb 20, 2017 2:59 AM
Author: Wally W.
Subject: Re: probably need to go to a 3rd power polynomial
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)