operator - solve

Forum|Forum|8 years ago
July 10, 2017
2 replies
6728 views

Hi

Please help me to find the h value using operator and solve h. I got 4 answers . How can I select the absolute value from the answers.

Other

Best answer by Werner_E

What I see in the pictures is that in the first case (=15 mm) is that for values of b greater than 2,2 m the solve block returns the negative solution from time to time. The solution returned depends on the guess value. fortunately in your case its easy - simply chose a greater value as guess. I have chosen 5m and all seems to work OK.

For the second case I can't duplicate your result

Fortunately simply enlarging the guess value seems to cure it here, too:

W

Werner_E

25-Diamond I

@ldante wrote:

Hi

Please help me to find the h value using operator and solve h. I got 4 answers . How can I select the absolute value from the answers.

Four solutions seem OK for me for that equation. How many solutions did you expect?

And what do you mean by "select absolute value from the answers"?

Do you mean how to select the postive of the four (if there is any or only one).

Answer: You cant, as we don't know anything about the other variables WL, b, E, Ixx, mm in use. They could be positive, negative, non-real and all that would change the output. Also the relatives magnitudes of the variables matter. So Prime can't decide, which of the four solutions is postive or even real.