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[49/50G] convert rectangular to exact polar - Printable Version

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[49/50G] convert rectangular to exact polar - BINUBALL - 03-13-2021 12:43 PM

This calculator doesn't support exact polar mode, but we know this formula.
[Image: 9e2ddd37957ce679debc878aeae5b9b4.png]
According to formula, first set calculator angle mode to polar.
[attachment=9209]
And enter complex number which you want to convert to polar.
[attachment=9210]
Press RS+4 and expand, boom! We get the exact answer!
[attachment=9211]
So, \(2+3i = \sqrt{13} \angle{ atan2(\frac{3}{2})}\)
(edited : arctan -> atan2)
If you want to convert a+bi to polar form, there needs more trick. Pull (a+bi)^c on stack and expand.
[attachment=9213]
a+bi = (a+bi)^1, so c=1 SUBST, and press EXP2POW, then you get a answer.
[attachment=9214]
I see expand to polar method somewhere in this forum, but a+bi convert method is made for myself. Maybe?

RE: [49/50G] convert rectangular to exact polar - Albert Chan - 03-13-2021 08:18 PM

FYI, phase angle of a+b*i = atan2(b,a), not atan(b/a)
The latter only covered phase angle between ±pi/2

RE: [49/50G] convert rectangular to exact polar - BINUBALL - 03-14-2021 11:32 AM

(03-13-2021 08:18 PM)Albert Chan Wrote:  FYI, phase angle of a+b*i = atan2(b,a), not atan(b/a)
The latter only covered phase angle between ±pi/2
Thanks for information. I only thought about the quadrant I. edited.

RE: [49/50G] convert rectangular to exact polar - Gil - 03-14-2021 02:34 PM

I wrote in polar mode (2,3) EXP And, but (2,3) has remained unchanged.

Any clue of what I missed?

Thanks and regards,
Gil

RE: [49/50G] convert rectangular to exact polar - BINUBALL - 03-14-2021 11:14 PM

(03-14-2021 02:34 PM)Gil Wrote:  I wrote in polar mode (2,3) EXP And, but (2,3) has remained unchanged.

Any clue of what I missed?

Thanks and regards,
Gil
You have to write EXACT complex number, so not (2,3). You have to write 2+3i.

And I think if you write (2,3) in polar mode, It has to change like this : (3.61<0.98). (In radian)

RE: [49/50G] convert rectangular to exact polar - Gil - 03-15-2021 02:16 AM

I tried with -27 flag, but (2+3*i) EXPAND still gives (2+3*i).

Well...

RE: [49/50G] convert rectangular to exact polar - BINUBALL - 03-15-2021 11:25 AM

(03-15-2021 02:16 AM)Gil Wrote:  I tried with -27 flag, but (2+3*i) EXPAND still gives (2+3*i).

Well...
My Flag list is { #7080018207A58FF0h # 0h # 905440430A038398h # 0h }. you can change to my flag setting to pull this on stack and execute STOF.

And.. My Clues are,
On header, There must be RAD R<Z (Base setting) C= (VX). CAS MODE must be clear except complex. Then execute 2+3*i EXPAND.

Does EXPAND still give nothing?

RE: [49/50G] convert rectangular to exact polar - Gil - 03-15-2021 12:00 PM

Pefect!
Very nice indeed.

Thanks and regards,
Gil