hi all,

> e0 := -21+.7*I;
                          -21. + 0.7 I
> e2 := e0;
                          -21. + 0.7 I
> e1 := 3.9;
                              3.9
> e3 := 1;
                               1
> t1 := 10*10^(-9);
                               1    
                           ---------
                           100000000
> t2 := 50*10^(-9);
                               1    
                            --------

hi all,

m := 1+(-21+.7*I)*sqrt((2.3*6.494)*10^13-x^2)/(2.3*sqrt(((-21+.7*I)*6.494)*10^13-x^2))

fsolve(m = 0, x, {x = 10^7+26500*I .. 2*10^7+26600*I}, complex)

the above characteristic equation m=0 will give complex roots if we solve it. but fsolve is not able to solve this equation evenif i provided the range.through some light for my problem.

thanks