0
$\begingroup$
variable[[i]]-(1/Pi)((t/2 - 1)*(Pi-2Sqrt[t-1]+2/3(t-1)^(3/2))+(-1+4/(3t)+4/(3t^2))Sqrt[(t-1)])==0 

This is the equation but the problem is that the solution is also complex and I need only the real solution of this equation. I try also with reduce :

Reduce[{variable[[3]] - 1/Pi((t/2 - 1)*(Pi-2Sqrt[t-1]+2/3(t-1)^(3/2))+(-1+4/(3t)+4/(3t^2))*Sqrt[(t-1)])==0}, 
  t, Reals]

and I get this error code

Reduce::ratnz: Reduce was unable to solve the system with inexact coefficients. The answer was obtained by solving a corresponding exact system and numericizing the result

Help me please.

$\endgroup$
  • $\begingroup$ Could you please post a complete minimal example ? What are variable[[i]], variable[[3]] ? $\endgroup$ – b.gates.you.know.what Nov 21 '18 at 14:53
  • $\begingroup$ variable[[i]] is a number taken from a table, is just a number of a table of 283 elements and i have to solve the equation (or reduce it) for all the 283 number. $\endgroup$ – Achille Angrisani Armenio Nov 21 '18 at 15:11
  • 1
    $\begingroup$ Use Rationalize[variable[[i]]] $\endgroup$ – Alex Trounev Nov 21 '18 at 15:35
  • $\begingroup$ thanx for the answer, if i use Solve instead of Reduce, i get the solution, both Complex and Real but in any cases i can not obtain only the Real solution of the equation i have no idea how i can extract only the Real solution $\endgroup$ – Achille Angrisani Armenio Nov 21 '18 at 15:39
  • 1
    $\begingroup$ Solve[x^5 - 2 x^2 + 1 == 0 && x ∈ Reals, x] -- Note Reduce::ratnz is a warning, not strictly an error. $\endgroup$ – Michael E2 Nov 21 '18 at 16:35

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Browse other questions tagged or ask your own question.