Why The function APP failled to find an extremum in this case - Printable Version +- HP Forums (https://www.hpmuseum.org/forum) +-- Forum: HP Calculators (and very old HP Computers) (/forum-3.html) +--- Forum: HP Prime (/forum-5.html) +--- Thread: Why The function APP failled to find an extremum in this case (/thread-5135.html) Why The function APP failled to find an extremum in this case - dg1969 - 11-15-2015 10:03 AM Good morning dear "Primers", Can you explain why the function App failed if i ask for an extremum of $$f(x)$$? $$f(x)=\frac{1}{9} \cdot (84\cdot x e^{-3\cdot x}-2 e^{-3\cdot x}+2)$$ Code: f(x):=1/9*(84*x*e^(-3*x)-2*e^(-3*x)+2) 1) I create $$f(x)$$ in CAS side. Have you notice the Latex command ? Did you know that ? ! CTRL+C CTRL+V to paste on these post !!! ;o) Thank's to M. PARISSE ! 2) I choose F1(X)=f(X) Here notice that the EVAL softKey do nothing !? Why ? 3)Plot and choose "EXTREMUM" 4) Can't find an extremum !! [/code] Thank's for reading. Didier RE: Why The function APP failled to find an extremum in this case - primer - 11-15-2015 11:20 AM Hi, in CAS environment, you have to type F1:=f instead, and it should work. RE: Why The function APP failled to find an extremum in this case - dg1969 - 11-15-2015 02:53 PM (11-15-2015 11:20 AM)primer Wrote:  Hi, in CAS environment, you have to type F1:=f instead, and it should work. Thank you , it works. But I continue to think that there is something to improve...