TICALCS.net

Has anyone been able to use the TI-Nspire CAS to solve for equations with multiple unknowns like the TI-89 Titanium? I am in engineering and have lost (stolen?) the TI-89 that I had.

Example, I was able to input this equation inth the 89 and solve for any variable using the numberical solver.
How can I do this on the nspire?
Z=sqrt( r^2 + (XL - XC)^2) and be able to solve for any variable.

Even programming I cannot get the program to ask for a variable input becasue there is not input command?

Should I return the calculator from where I purchased it and buy someting else?

Is the TI-Nspire doomed to be only good for Functions or programs that do not require any user input?

Anyone?

I'm not sure, although I'm guessing there would be a way to pass arguments to functions/programs and then run it by doing something like: myFunc(1,2). Texas Instruments did limit the Nspire CAS's on-calculator programming capabilities a lot, though, and assembly/machine code can't be written on the Nspire CAS at all (as of now).

I think there's a way to solve systems of equations using matrices that is fairly simple, although I don't know remember exactly how to do it any more (these pages I just found look like they might be helpful though: 1 2). Vladik and some other members here would probably know how.

Solving for multiple variables and multiple equations is easy
I just typed in
solve(x+y=12 and x-y=18,{x,y})
and got x=15 and y=−3
Note the use of the curley brackets for specifying { x, y}, also the use of "and"
By the way, this works on the -89 also. Works for 3 variables, 3 equations also.