Error in solving equation
03-07-2022, 01:57 AM
Post: #1
 yingwuluo Junior Member Posts: 32 Joined: Aug 2017
Error in solving equation

Error in solving equation
The program always selects all variables by default. You need to select the variables you need one by one. Can you not select all variables by default?
Post: #2
 roadrunner Senior Member Posts: 446 Joined: Jun 2015
RE: Error in solving equation
The issue is the second page of variables. It appears that the solver app only supports up to 12 variables, you have 16. The second page of variables isn't being counted or looked at.

To solve your system I created the app variables, then did the following:

in cas:
'SIGEMA=ES*KESICU*((B1*H0/X)-1)'▶E1
'N=A1*FC*B*X+FY*AS-SIGEMA*AS'▶E2
'N*E=A1*FC*B*X*(H0-(X/2))+FY*AS*(H0-BHC)'▶E3
'E=(M/N)+MAX(20,(H/30))+(H/2)-BHC'▶E4

Uncheck E1, E2, E3 and leave only E4 checked.
Solve for E which give 435.
Edit E3 by replacing E with 435 and BHC with 35 which give you:
N*435=A1*FC*B*X*(H0-(X/2))+FY*AS*(H0-35) stored in E3
Finally, uncheck E4, check only E1, E2, and E3, then solve for SIGEMA, X, and AS since there are now only 12 variables in the first 3 equations.

I got SIGEMA = 257.34, X = 115.12, and AS = 13067, but there are other solutions as well.

Here are two screen shots showing what I did:

03-10-2022, 01:20 AM
Post: #3
 yingwuluo Junior Member Posts: 32 Joined: Aug 2017
RE: Error in solving equation
03-10-2022, 01:54 AM
Post: #4
 yingwuluo Junior Member Posts: 32 Joined: Aug 2017
RE: Error in solving equation
(03-09-2022 04:08 PM)roadrunner Wrote:  The issue is the second page of variables. It appears that the solver app only supports up to 12 variables, you have 16. The second page of variables isn't being counted or looked at.

To solve your system I created the app variables, then did the following:

in cas:
'SIGEMA=ES*KESICU*((B1*H0/X)-1)'▶E1
'N=A1*FC*B*X+FY*AS-SIGEMA*AS'▶E2
'N*E=A1*FC*B*X*(H0-(X/2))+FY*AS*(H0-BHC)'▶E3
'E=(M/N)+MAX(20,(H/30))+(H/2)-BHC'▶E4

Uncheck E1, E2, E3 and leave only E4 checked.
Solve for E which give 435.
Edit E3 by replacing E with 435 and BHC with 35 which give you:
N*435=A1*FC*B*X*(H0-(X/2))+FY*AS*(H0-35) stored in E3
Finally, uncheck E4, check only E1, E2, and E3, then solve for SIGEMA, X, and AS since there are now only 12 variables in the first 3 equations.

I got SIGEMA = 257.34, X = 115.12, and AS = 13067, but there are other solutions as well.

Here are two screen shots showing what I did: