Error on my Prime G2

[Quadratica]

HP Prime G2 in radians (home or CAS)

1. tan(45)......no problem
2. cos(56).......no problem
3. tan(45)-cos(56).......fails to evaluate it, hour glass appears and it freezes
4. tan(44)-cos(56)........takes about 10 seconds to evaluate.

I reset but it still happens. Does anyone else have this issue and is there a fix?

[Nigel (UK)]

This happens for me on my Windows Prime app, but only in CAS mode, with Exact Mode ticked in Settings, and Simplify set to Maximum. It doesn't happen if one or both of the angles has a decimal point added - e.g., \(\tan(45.)-\cos(56)\).

I expect that since you have entered an exact expression (no decimals) the CAS is trying to simplify it using trig identities, and is taking a long time to do this. On my computer clicking on the Esc key does interrupt the process, showing an expression involving huge integers and a polynomial of order 101 in \(\cos(1)\).

One way around this is to set Simplify to Minimum (or Off), or make your angles approximate by adding decimal points. I'm not sure it counts as a bug, though others may disagree!

Nigel (UK)

[Insoft]

Tested it on CAS mode on my Prime G2

tan(45)-cos(56)
gives me
-cos(56)+tan(45)

Software Version: 2.1.14730 (2023 04 13)
Hardware Version: D
CAS Version: 1.5.0

OS: V2.060.650

only if I tap on simplify will it give me hour glass, require me to terminate by holding down the On/Off KEY

[Rigel]

No problem on my G2 on home and CAS pages in rad or degree modes. . The result is displayed instantly. Software version 2.1.14730 (most recent).

[Quadratica]

Thanks for that info.

Tried it with the decimal point and it worked and then set simplify to minimum and it gave -cos(57) + tan(45)....what oddities.

software is 2.1.12603 (2021)

Just go this calc (long time ti nspire CAS user since 2011!)

Trying to update by using latest firmware and connectivity kit (Windows) but when I run the CK it gives three options:

repair, uninstall, close

tried numerous times with same result. So what now, and is it worth updating, are there any real daily use benefits in having the 2023 version. I do mostly CAS stuff at university level.

[Quadratica]

Thanks, tried the decimal point and setting simplify to minimum and both worked. What oddities which I never had on the ti nspire CAS

now having issue with connectivity kit, after installing and then running it says:

repair uninstall close

I'm trying to upgrade from 14603 to latest firmware.

Are there any real, daily-use benefits in the latest firmware (I do mostly university level maths)

[Quadratica]

All sorted now. Thanks for all the help.

[parisse]

If you try to simplify trigonometric expressions like simplify(tan(45)-cos(56)) in radians mode (this is the default inside CAS, I guess it's not what you expected), the CAS will rewrite it in "normal" form, it takes the integer gcd of the arguments of 45 and 56, and rewrites everything with sin/cos of the gcd. This normal form helps deciding if an expression is 0 or not, e.g. simplify(tan(2)-sin(2)/(2*cos(1)^2-1)) will return 0, a floating point computation like tan(2.0)-sin(2)/(2*cos(1)^2-1) would not return 0, but a small value.
Here the gcd of 45 and 56 is 1, therefore you will get a huge rational expression in terms of cos(1) and sin(1), see at the bottom.
I do not recommend setting simplify to maximum in the settings, especially if you are a beginner with CAS mode, it's easy to call simplify with the menu at the bottom of the screen. I would also recommend to stay in HOME mode if you are doing purely numeric computations in degree mode.

Code:

(-633825300114114700748351602688*cos(1)^101+16004088827881396193895877967872*cos(1​)^99-196050088141547103375224505106432*cos(1)^97+1552396616304495430807900162883584*c​os(1)^95-8932282077061304250718136890818560*cos(1)^93+39804482005904437067262697519710208​*cos(1)^91-142981889310683043675825216090537984*cos(1)^89+425468904666135865527759533594640​384*cos(1)^87-1069676863142482710308701891920396288*cos(1)^85+23060062810499174370785421220747​67360*cos(1)^83-4311724930996081889218834528252985344*cos(1)^81+70555498870844976369035474098685​21472*cos(1)^79-10177036143308678473454976390358106112*cos(1)^77+1301486352942359843239915249920​7962624*cos(1)^75-14826045276744862746267507465230745600*cos(1)^73+1510187867724244158805853085993​2712960*cos(1)^71-13797120776818921818502003377548820480*cos(1)^69+1133334920952982863662664563155​7959680*cos(1)^67-8386223260465345085535981757488168960*cos(1)^65+55979924203363022393821701076942​84800*cos(1)^63-3374345431147159960960919203804610560*cos(1)^61+18378131366069353358805006377864​39680*cos(1)^59-904631264883333245020580147080724480*cos(1)^57+402394509128706761163000533651292​160*cos(1)^55-161676365274926823681562714413465600*cos(1)^53+586289556181182007982087948583567​36*cos(1)^51-19167158567461719491722106011385856*cos(1)^49+5640785404237983514080379546894336​*cos(1)^47-1491606903615768145479669836152832*cos(1)^45+17592186044416*cos(1)^44*sin(1)+353​613705598565724143887245639680*cos(1)^43-189115999977472*cos(1)^42*sin(1)-74956144637442452793880324603904*cos(1)^41+946679511515136*cos(1)^40*sin(1)+1416​2220876198804444926697275392*cos(1)^39-2930198488023040*cos(1)^38*sin(1)-2376405269307815691506042273792*cos(1)^37+6280272978903040*cos(1)^36*sin(1)+3526​48375525625055825094508544*cos(1)^35-9891429941772288*cos(1)^34*sin(1)-46054825161928645350292193280*cos(1)^33+11857034609688576*cos(1)^32*sin(1)+52634​08589934702325747679232*cos(1)^31-11054678884220928*cos(1)^30*sin(1)-522966879128127474673647616*cos(1)^29+8122948166615040*cos(1)^28*sin(1)+44832042​425257549560283136*cos(1)^27-4738386430525440*cos(1)^26*sin(1)-3286559501099707580547072*cos(1)^25+2199965128458240*cos(1)^24*sin(1)+2038808623​51098485145600*cos(1)^23-811751838842880*cos(1)^22*sin(1)-10570052904677851791360*cos(1)^21+236760952995840*cos(1)^20*sin(1)+4511607947118​59527680*cos(1)^19-54068006092800*cos(1)^18*sin(1)-15566686016087162880*cos(1)^17+9530420428800*cos(1)^16*sin(1)+424432497631887360​*cos(1)^15-1270722723840*cos(1)^14*sin(1)-8884651565260800*cos(1)^13+124607508480*cos(1)^12*sin(1)+137500559938048*cos(1)^​11-8638755840*cos(1)^10*sin(1)-1494571302272*cos(1)^9+399942400*cos(1)^8*sin(1)+10599795072*cos(1)^7-11334400*cos(1)^6*sin(1)-43748544*cos(1)^5+170016*cos(1)^4*sin(1)+85740*cos(1)^3-1012*cos(1)^2*sin(1)-45*cos(1)+sin(1))/(17592186044416*cos(1)^45-197912092999680*cos(1)^43+1039038488248320*cos(1)^41-3380998255411200*cos(1)^39+7638169839206400*cos(1)^37-12717552782278656*cos(1)^35+16168683558666240*cos(1)^33-16047114509352960*cos(1)^31+12604574741299200*cos(1)^29-7897310717542400*cos(1)^27+3959937231224832*cos(1)^25-1588210119475200*cos(1)^23+507344899276800*cos(1)^21-128055803904000*cos(1)^19+25227583488000*cos(1)^17-3812168171520*cos(1)^15+431333683200*cos(1)^13-35340364800*cos(1)^11+1999712000*cos(1)^9-72864000*cos(1)^7+1530144*cos(1)^5-15180*cos(1)^3+45*cos(1))