TI Nspire ii CX CAS help

Oct 2019
3
1
Florida
Hello,

I have a basic circuit in which I am trying to enter both my KCL and KVL equations into my TI Nspire calculator using the "systems of equations" option. I keep getting a "False" for the answer. I am trying to solve for the three variables: is, ia, ib.

The equations are:

Equation#1 KCL at Top Node: -is+ia+ib=0
Equation#2 KVL @ Left Node: -200+is(4)+ia(20)=0
Equation#3 KVL @ Right Loop: ib(80)-ia(20)=0

When I tell Maxima to solve ([ ia + ib - is = 0, 4*is + 20*ia - 200 = 0, 80*ib - 20*ia = 0 ], [ia, ib, is]);
it tells me there is exactly one answer,
[[ ia = 8, ib = 2, is = 10 ]]
Maple agrees, too.

Thank you all for your help,

CJ
 
Oct 2019
3
1
Florida
Thank you. I found that you must use * in place of () if there are more thsn two variables.
 
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Oct 2019
3
1
Florida
I do not see a 1/x or x^-1 key. What is the simplest method to type a number in and get 1/that number? Thank you.
 
Dec 2014
119
96
USA
type 1, then the division key, then the number ... output is the first fraction shown

type (ctrl), then the division key ... you get a formatted fraction to fill in the numerator and denominator, second "fraction" shown

you may also type the number, then the caret key, then type in -1 for the exponent
Nspire frac.jpg
 
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