Solving 2 parameters equation

Hi everyone,

my unknown parameters are D and nR, I want Rg will be less than 0.5

How is it possible?

      p=100;
      pi=3.14;
      asec=0.2179;
      k1=1.3663;
      Lg=35;
      Wg=32;
      k2=5.6641;
      Lr=3;
      b=0.01;

R1=((p/(pi*Lc))*(log((2*Lc)/asec)+((k1*Lc)/sqrt(Lg*Wg))-k2));

R2=((p/(2*pi*nR*Lr))*(log((4*Lr)/b)-1+((2*k1*Lr)/(sqrt(Lg*Wg)))*(((sqrt(nR)- 1))^2)));

Rm= ((p/(pi*Lc))*(log((2*Lc)/Lr)+((k1*Lc)/sqrt(Lg*Wg))-k2+1));

Rg=((R1*R2)-(Rm^2))/((R1+R2)-(2*Rm));

Thank you.

Answer 1

[Roger Stafford]

I see no unknown variable ‘D’ here. Also the variable ‘Lc’ is not defined. Do you mean that Lc and nR are actually the two unknowns? Also you need to specifically define ‘Rg’.

This looks as though it calls for ‘fsolve’:

   http://www.mathworks.com/help/optim/ug/fsolve.html

[Hamid]

My bad,sorry

    Na=(Lg/D)+1;
    Nb=(Wg/D)+1;
    Lc=(Lg*Nb)+(Wg*Na);

my unknown parameters are D and nR, I want Rg will be less than 0.5.

please write the right code for solving the equation, unfortunately I don't have enough time.

Thanks.