Taylor Expansion not working - Printable Version +- HP Forums (https://www.hpmuseum.org/forum) +-- Forum: HP Calculators (and very old HP Computers) (/forum-3.html) +--- Forum: General Forum (/forum-4.html) +--- Thread: Taylor Expansion not working (/thread-4524.html) Taylor Expansion not working - wneff - 08-14-2015 05:38 PM Hello, I have been a long time user of the 48SX and GX and just got a 50g to replace the SX. So....and now I want to do a taylor expansion of sqrt(0.2*x+1) So...first when i assemble the root is asks me to turn on approx mode - OK I put on the stack > sqrt(etc) >'X' >5 and i get the message: "Approx mode off" ...OK... Next it s pop-up: "TAYLR error: Mode switch not allowed here " hmmmmm.....works on the SX. Can someone give me a hint how to do that? Wolfram RE: Taylor Expansion not working - Gerson W. Barbosa - 08-14-2015 06:54 PM Try replacing 0.2*X with X/5 RE: Taylor Expansion not working - wneff - 08-14-2015 07:25 PM (08-14-2015 06:54 PM)Gerson W. Barbosa Wrote:  Try replacing 0.2*X with X/5 Ok, this equation was just an example ..i actually need (0.000231*x+0.1296480889)^0.5 RE: Taylor Expansion not working - Gerson W. Barbosa - 08-14-2015 08:33 PM (08-14-2015 07:25 PM)wneff Wrote:   (08-14-2015 06:54 PM)Gerson W. Barbosa Wrote:  Try replacing 0.2*X with X/5 Ok, this equation was just an example ..i actually need (0.000231*x+0.1296480889)^0.5 In exact mode, '√(231/1000000*X+1296480889/10000000000)' 'X' 3 TAYLR --> '5788125000*√1296480889/1637269993841868597755699*X^3-55125*√1296480889/13891427235886201*X^2+21*√1296480889/2357237980*X+√1296480889/100000' You might need to set flag -79 (Textbook off). HTH, Gerson. RE: Taylor Expansion not working - wneff - 08-14-2015 09:37 PM (08-14-2015 08:33 PM)Gerson W. Barbosa Wrote:   (08-14-2015 07:25 PM)wneff Wrote:  Ok, this equation was just an example ..i actually need (0.000231*x+0.1296480889)^0.5 In exact mode, '√(231/1000000*X+1296480889/10000000000)' 'X' 3 TAYLR --> '5788125000*√1296480889/1637269993841868597755699*X^3-55125*√1296480889/13891427235886201*X^2+21*√1296480889/2357237980*X+√1296480889/100000' You might need to set flag -79 (Textbook off). HTH, Gerson. Super that worked! Thanks a lot. Now - this seems weird to me that it can't just give me the polynomila numbers as decimals - is there a way to chenage settings to get that done? RE: Taylor Expansion not working - Dalil - 08-17-2015 05:16 PM Hello, I believe you can use the ->Q command under the Convert>Rewrite menu to do the conversion from decimal to fractional automatically, at least it seems to be working on your example, giving Code: `sqrt(1/4329*X+129/995)` After that you could perform the Taylor expansion. Hope this help.