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Topic: improvement on sin(x) = −0.4176x^2 +1.3122x -
0.0504 ;; we need semicircle sine, not the fakery of sinusoi
d sine

Replies: 15   Last Post: Feb 25, 2017 3:31 AM

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abu.kuanysh05@gmail.com

Posts: 3,654
Registered: 2/21/15
Re: cosine is Y = -1.44x^2 + .44x + 1 Re: sine is Y= -1.44x^2 + 2.44x
Posted: Feb 25, 2017 3:31 AM
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hm, w0w, wierd, why?

> atan2(Y,X) = slope of angle between hypothenuse and
> adjacent in a right triangle where
> oposite has length Y and adjacent has
> length X plus complication that the
> lengths can have a negative sign.
> https://en.wikipedia.org/wiki/Atan2

> > what is atan2(.,.) ??
> > > > asin(X) = atan2(X, sqrt(1-X^2))
> > > > acos(X) = atan2(sqrt(1-X^2), X)



Date Subject Author
2/19/17
Read Re: improvement on sin(x) = −0.4176x^2 +1.3122x -
0.0504 ;; we need semicircle sine, not the fakery of sinusoi
d sine
bursejan@gmail.com
2/19/17
Read Experimenting sin(x)= -.4x^+1.6x -.09, cos(x)= -.6x^2 -.3x +1
plutonium.archimedes@gmail.com
2/19/17
Read can these two formula work Re: Experimenting sin(x)= -.4x^2+1.6x
-.09, cos(x)= -.6x^2 -.3x +1
plutonium.archimedes@gmail.com
2/20/17
Read if quadratic works for circle, ditto semicircle Re: Experimenting
sin(x)= -.4x^2+1.6x -.09, cos(x)= -.6x^2 -.3x +1
plutonium.archimedes@gmail.com
2/20/17
Read probably need to go to a 3rd power polynomial
plutonium.archimedes@gmail.com
2/20/17
Read Re: probably need to go to a 3rd power polynomial
Wally W.
2/20/17
Read Re: probably need to go to a 3rd power polynomial
abu.kuanysh05@gmail.com
2/20/17
Read why sine in Old Math is fakery Re: probably need to go to a 3rd power polynomial
plutonium.archimedes@gmail.com
2/20/17
Read sine is -1.44x^2 + 2.44x + 0 = Y
plutonium.archimedes@gmail.com
2/20/17
Read cosine is Y = -1.44x^2 + .44x + 1 Re: sine is Y= -1.44x^2 + 2.44x
plutonium.archimedes@gmail.com
2/20/17
Read Re: cosine is Y = -1.44x^2 + .44x + 1 Re: sine is Y= -1.44x^2 + 2.44x
bursejan@gmail.com
2/20/17
Read Re: cosine is Y = -1.44x^2 + .44x + 1 Re: sine is Y= -1.44x^2 + 2.44x
thugstyle103@gmail.com
2/20/17
Read Re: cosine is Y = -1.44x^2 + .44x + 1 Re: sine is Y= -1.44x^2 + 2.44x
thugstyle103@gmail.com
2/20/17
Read Re: cosine is Y = -1.44x^2 + .44x + 1 Re: sine is Y= -1.44x^2 + 2.44x
bursejan@gmail.com
2/25/17
Read Re: cosine is Y = -1.44x^2 + .44x + 1 Re: sine is Y= -1.44x^2 + 2.44x
abu.kuanysh05@gmail.com

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