solving an equation in MATLAB

Hi,

I am trying to solve the following equation for q in MATLAB, however, I get a message saying q is not defined.

solve(z1*(K1-1)/(q*(K1-1)+1)+z2*(K2-1)/(q*(K2-1)+1)+z3*(K3-1)/(q*(K3-1)+1)==0,q)

Answer 1

[Matt Fig]

   S = solve('z1*(K1-1)/(q*(K1-1)+1)+z2*(K2-1)/(q*(K2-1)+1)+z3*(K3-1)/(q*(K3-1)+1)','q')

Answer 2

[KeJoSa]

Thanks Matt!

Answer 3

[Walter Roberson]

No, the key is to add

syms q

before the call.

Also, as you are not using R2012a or later, you cannot use == in solve(). As you are comparing to 0 anyhow, just leave that part out:

solve(z1*(K1-1)/(q*(K1-1)+1)+z2*(K2-1)/(q*(K2-1)+1)+z3*(K3-1)/(q*(K3-1)+1),q)

[Matt Fig]

What do you mean, 'No' Walter? The above code works fine on my system....