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Solving with the built-in equations of the 35s - Printable Version

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Solving with the built-in equations of the 35s - Palmer O. Hanson, Jr. - 10-15-2012

Page 7-6 of the 35s manual describes use of the built-in equations from the keyboard. I would like to use the "2x2 lin solve" equation in a program. How do I do that?


Re: Solving with the built-in equations of the 35s - Gene Wright - 10-16-2012

This should show how. Good to finally meet you a few weeks ago in Nashville!

Learning Module


Re: Solving with the built-in equations of the 35s - Andrew Feist - 10-16-2012

I don't think you do--I think you can only type your own equations into a program, not use the ones that are built in.


Re: Solving with the built-in equations of the 35s - Gene Wright - 10-16-2012

Ah, I mis-read your original question.

You cannot use one of the built-in equations in a user program. Sorry!


Re: Solving with the built-in equations of the 35s - Dieter - 10-17-2012

You cannot use equations from the 35s equation list in your own programs. But solving a 2x2 system is so trivial that it can be done in a very short user routine:

RCL A
RCL* F
RCL D
RCL* C
-
RCL A
RCL* E
RCL B
RCL* D
-
/
ENTER
RCL* B
+/-
RCL+ C
RCL/ A
This returns the two unknowns in X and Y.

Actually you can also do this in just two lines, using the EQN-feature:

([A,D]*[F,-C])/([A,B]*[E,-D]>G)
([C,B]*[E,-F])/G
Type "STO G" to enter ">G". Please also note that the minuses are unary (signs, not operators). This solution also works for A=0. ;-)

Dieter

Edited: 17 Oct 2012, 3:28 p.m.