clear all; 



tauL = 2.5e-6;

tauP = 0.1e-6;

r = linspace(95,105,1e5);



disc = (r-1)/(tauL*tauP)-(r/(2*tauL)).^2;

plot(r,disc);

grid on;

[m mIndex] = min(abs(disc));

r0 = r(mIndex);