Equa diff Help - Printable Version +- HP Forums (https://www.hpmuseum.org/forum) +-- Forum: HP Calculators (and very old HP Computers) (/forum-3.html) +--- Forum: HP Prime (/forum-5.html) +--- Thread: Equa diff Help (/thread-301.html) Equa diff Help - jc_63 - 01-01-2014 04:57 PM Hello, on HP Prime, when i enter in CAS mode : deSolve(y+2E-3*y'=0 AND y(0)=10,y) I get an error "bad arguments". How to define the diff operator ' or diff() ? Is there a special key to ' ? Thanks for your help. JC RE: Equa diff Help - Han - 01-01-2014 05:18 PM (01-01-2014 04:57 PM)jc_63 Wrote:  Hello, on HP Prime, when i enter in CAS mode : deSolve(y+2E-3*y'=0 AND y(0)=10,y) I get an error "bad arguments". How to define the diff operator ' or diff() ? Is there a special key to ' ? Thanks for your help. JC In CAS mode, use 2*10^(-3) and not 2E-3. RE: Equa diff Help - jc_63 - 01-01-2014 05:46 PM It's OK when i enter : desolve(y+2E-3*diff(y)=0 AND y(0)=10,y) > 10*e^(-500*x) y' is not correct ! Thanks, JC RE: Equa diff Help - jc_63 - 01-02-2014 09:04 PM I've found : the ' is in Chars (Shift Vars) and y' is correctly coded as diff(). With Shift 9, the ' is not the same but minute (angle unit). It is a source of error ! JC RE: Equa diff Help - Han - 01-02-2014 09:31 PM (01-02-2014 09:04 PM)jc_63 Wrote:  I've found : the ' is in Chars (Shift Vars) and y' is correctly coded as diff(). With Shift 9, the ' is not the same but minute (angle unit). It is a source of error ! JC An easier way to get ' is to use [Shift][ () ] and delete the extra tic mark.