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Taylor expanding with the HP50G - Gil - 09-28-2023 10:52 AM
I try to get the Taylor expansion of
x/ (4.76 + 0.83*x).
I put the above expression on the stack of the HP50G, then x, then 5 for instance and press TAYLR.
I get the followings message:
TAYLR Error:
Mode switch not allowed here.
Thanks for your help.
RE: Taylor expanding with the HP50G - dlidstrom - 09-28-2023 01:25 PM
It seems the TAYLR command prefers to work with whole numbers for exact answers. You may try a symbolic version of your equation. I substituted your decimals with A and B and it worked fine. To evaluate the equation you need to store the values in A and B respectively.
RE: Taylor expanding with the HP50G - Nigel (UK) - 09-28-2023 02:32 PM
If you don’t want to use extra variables A and B you can replace the decimals with fractions e.g., write 0.83 as 83/100.
Nigel (UK)
RE: Taylor expanding with the HP50G - Gil - 09-28-2023 07:57 PM
Thanks a lot to both of you, the given solutions worked.
I did for instance:
'X/(476/100+83/100*X)' X 5
TAYLR
And got:
'-98476016075/2907915115807744*X^6+1186458025/6109065369344*X^5+-14294675/12834170944*X^4+172225/26962544*X^3+-2075/56644*X^2+25/119*X'
Which command(s) could I use to get, if possible in one single step, the execution of :
98476016075/2907915115807744,
1186458025/6109065369344,
asf?
To get something simplified as
'-(3.38648179721E-5*X^6.+-1.9421269102E-4*X^5.+1.11379808344E-3*X^4.+-6.38756491227E-3*X^3.+3.66322999788E-2*X^2.+-.210084033613*X)'.
RE: Taylor expanding with the HP50G - Carsen - 09-29-2023 03:01 AM
Quote:Which command(s) could I use to get, if possible in one single step, the execution of :
98476016075/2907915115807744,
1186458025/6109065369344,
asf?
To get something simplified as
'-(3.38648179721E-5*X^6.+-1.9421269102E-4*X^5.+1.11379808344E-3*X^4.+-6.38756491227E-3*X^3.+3.66322999788E-2*X^2.+-.210084033613*X)'.
Simply switch to approximate mode and press the [EVAL] key on that object. Hope it helps.
RE: Taylor expanding with the HP50G - Steve Simpkin - 09-29-2023 04:41 AM
(09-29-2023 03:01 AM)Carsen Wrote: ...
Simply switch to approximate mode and press the [EVAL] key on that object. Hope it helps.
I tried switching the CAS to Approx mode first. When I executed TAYLR, it prompted "Approx. Mode off? YES NO". When I chose NO, it displayed the following error message.
[attachment=12597]
RE: Taylor expanding with the HP50G - Carsen - 09-29-2023 05:43 AM
(09-29-2023 04:41 AM)Steve Simpkin Wrote: I tried switching the CAS to Approx mode first. When I executed TAYLR, it prompted "Approx. Mode off? YES NO". When I chose NO, it displayed the following error message.
Let me explain more clearly.
Execute the TAYLR command in exact mode to get a symbolic answer.
Then switch to approximate mode and press the [EVAL] key on the keyboard to turn the symbolic answer into an approximate one.
RE: Taylor expanding with the HP50G - Gil - 09-29-2023 07:07 AM
Thanks, Carsen.