Solving equation without syms

I am trying to solve these equation and dont have access to syms:

I want to get V from 1 and b from 2 for each value of P and rest are constants.

P = C^2(V0-V)/(V0-S(V0-V))^2 .... everything except V is known, P is an array from 0 to 100;

P = Q*b^2/3{exp[q(1-b^(-1/3))]-b^(2/3)}, same P is from 1-100, everything except b is known.

Thanks in advance

Answer 1

[Torsten]

For the first equation:

Build the polynomial of degree 3 in V with pencil and paper, give numerical values to S,V0,C and P and use Matlab's "roots" to solve for V.

For the second equation:

Give numerical values to all parameters except b and use "fzero" or "fsolve" to solve for b.

[Rajkrishna Dutta]

Thank you!

1. ok
2. Can you please help with how to setup fsolve? I am new to this.

PS: I want to solve these for every value of P.

[Torsten]

P = 1:100;

q = ...;

Q = ...;

b0 = 1.0;

for i=1:numel(P)

p = P(i);

fun = @(b)p-Q*b^2*(exp(q*(1-1/b))-b^2);

b(i) = fzero(fun,b0);

b0 = b(i);

end

P = P(b>=0);

b = b(b>=0);

b = b.^3

plot(P,b)

[Rajkrishna Dutta]

Thank you, will try.