Problem with casio 991 es

SOURCE: Can I convert Decimal Degrees

Yes. Pressing the DMS key (two keys above the 8 key) when a result is displayed toggles the result between decimal degrees and degrees-minutes-seconds.

For example, to convert 3.5 degrees, press 3 . 5 = and you'll see 3.5. Now press DMS and you'll see 3 degrees 30 minutes 0 seconds.

SOURCE: can you show how to convert pola to rectangular o

Hello,
To avoid errors make sure that the angle unit is THE ONE required by your problem. To verify or to change the angle unit press [SIFT][MODE] and select [3: Deg] for degrees, [4:Rad] for radians, or [5:Grad] for grads.

Convert from rectangular to polar

[SHIFT][+] (Pol) . Screen displays Pol(
You enter the X-coordinate, and the Y coordinate separated by a comma, then you close the parenthesis and press [=].

Exemple: Polar coordinate of the point (1,1)
Pol( 1, 1) gives
r=1.414213562 (square root of 2)
θ=45

Here is how you enter it
Press [SHIFT][MODE][2:LineIO]
[SHIFT][POL] 1 [SHIF] [,] 1 [)] [=]

The screen displays
Pol(1,1)
r= 1.414213562
θ= 45

Convert from polar to rectangular coordinates

Rec ( radius, angle) =

Exemple: Recatngular coordinates of (r=3, θ=60°)
[SHIFT][Rec] 3 [SHIFT][,] 60 [ ) ] [=]
The screen displays
Rec(3,60)
X= 1.5
Y= 2.598076211

Hope it helps.

Testimonial: "thanx that was very helpful"

SOURCE: convert from polar to rectangular

Examples #036 and #037 in the Appendix illustrate how to convert between polar and rectangular coordinates. If you need the appendix and/or the manual, you can download them from
http://support.casio.com/manualfile.php?rgn=1&cid=004001004