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+--- Thread: Solve function giving [ ] result (/thread-1250.html)
Solve function giving [ ] result - Rich - 05-06-2014 01:07 AM
Hello,
When trying to solve this equation i get a result of [], anyone else getting a similar result or perhaps can see an error in my method?
Trying to solve for x here:
348.4=269.65+.5*(315-269.65)+((x/26000)^2 + .25*(315-269.65)^2)^.5
I use the solve function:
solve('348.4=269.65+.5*(315-269.65)+((x/26000)^2 + .25*(315-269.65)^2)^.5', x)
and i get this result:
[]
Thanks
RE: Solve function giving [ ] result - parisse - 05-06-2014 06:52 AM
If you run solve on an equation with approx data, then fsolve is called instead. Since no interval or guess is provided, the solver tries bisection in tan(-1.57)..tan(1.57), but unfortunately the solutions are outside. You can either give a bisection interval and call fsolve, or run solve(exact(your_equation))
RE: Solve function giving [ ] result - Rich - 05-06-2014 12:12 PM
Using fsolve with an estimated starting point worked.
Thanks!