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how to find all roots of this non-linear equation in some range?


I can't figure how to tell Maple to give me all root of

 eq:=tan(sqrt(lam)*Pi)=sqrt(lam);

This is what I tried

 RootFinding:-Analytic(eq,lam,re=0..100,im=0..0);

Nothing

 Student:-Calculus1:-Roots(eq,0..100);

gives [0]

 fsolve(eq,lam,lam=0..100);

gives only one root 55.61535492

Is there other functions one can try? The roots are, using Mathematica:

   NSolve[Tan[Sqrt[lam] *Pi]==Sqrt[lam]&&0<lam<100,lam]

which gives

 {1.66438,5.63138,11.6225,19.6189,29.6171,41.616,55.6154,71.6149,89.6146}

How can one get the above result in Maple 2017.3?


Solution

  • restart;
    eq := tan(sqrt(lam)*Pi) = sqrt(lam):
    
    Student:-Calculus1:-Roots(eq, 0..100, numeric);
    
           [1.664382913, 5.631380410, 11.62250178, 19.61888190,
            29.61705752, 41.61601074, 55.61535492, 71.61491703,
            89.61461020]