How to solve a set of non-linear simultaneous equations using Matlab ?

Respected all,

I am looking for the code which is required to get the solution of a set of 7 non-linear simultaneous equations

Please help

Regards

Surabhi

I need to solve these:

a=1.1:0.1:2.3;
b=(2.*a)./(1+1.5.*((a).^2));
z=((1+2.*b).^2)-4.*b;
d=((1+2.*b)+((z).^(1/2)))./(2.*b);
c=((1+2.*b)-((z).^(1/2)))./(2.*b);
e=(((a+b)./b)-(((1.*(((d).^5)-(c).^5))-((d).^4-(c).^4))./b.*((((d).^6)-(c).^6))-(((d).^5-c.^5)))).^(-1);
q=0:1:12;
k=(((0.85).^((((0.85.*exp(-4)).^(1/2)).*4-(0.85.*exp(-4)).^(1/2))+2.*q))./((2+((0.85.*exp(-4)).^(1/2)).*4-(0.85.*exp(-4)).^(1/2))).*(0.85-1))./((0.85.^((((2.*(2+((0.85.*exp(-4)).^(1/2)).*4-(0.85.*exp(-4)).^(1/2))+(((0.85.*exp(-4)).^(1/2)).*4-(0.85.*exp(-4)).^(1/2)+q)./(2+((0.85.*exp(-4)).^(1/2)).*4-(0.85.*exp(-4)).^(1/2)))))-1)));
f=((b.*(1-e).*(1-e).*a.*(1-k)))./(1-k).*0.50;
t=f.*(1-k);
plot(q,t,'- r <');

[Walter Roberson]

I do not see 7 simultaneous equations. q=0:12 tells us that we are dealing with at least 13 simultaneous equations.

[surabhi sachdeva]

Sorry, sir.

You are right.

I need to solve these equations and get the different values of t. Is the coding right?

How to write a code for such?

Please help

Regards

[Walter Roberson]

Which are the 7 equations to be solved? Which are the 7 variables to be solved for?

You assign to 10 variables, including two variables that you assign specific numeric variables. If we treat your assignment to a and q as being bounds for a and q, then you have 8 variables assigned to, with a and q being the unknowns. Possibly your k is a temporary variable to help create f and t, but if so that would get you down to 6 equations.

[surabhi sachdeva]

You are absolutely right sir

I need to create t.

[surabhi sachdeva]

Sir,

Is the code ok?

Can you help me with it?

[Walter Roberson]

A = linspace(1.1, 2.3, 25);
Q = linspace(0, 12, 30);
[a, q] = ndgrid(A, Q);

b=(2.*a)./(1+1.5.*((a).^2));
z=((1+2.*b).^2)-4.*b;
d=((1+2.*b)+((z).^(1/2)))./(2.*b);
c=((1+2.*b)-((z).^(1/2)))./(2.*b);
e=(((a+b)./b)-(((1.*(((d).^5)-(c).^5))-((d).^4-(c).^4))./b.*((((d).^6)-(c).^6))-(((d).^5-c.^5)))).^(-1);
k=(((0.85).^((((0.85.*exp(-4)).^(1/2)).*4-(0.85.*exp(-4)).^(1/2))+2.*q))./((2+((0.85.*exp(-4)).^(1/2)).*4-(0.85.*exp(-4)).^(1/2))).*(0.85-1))./((0.85.^((((2.*(2+((0.85.*exp(-4)).^(1/2)).*4-(0.85.*exp(-4)).^(1/2))+(((0.85.*exp(-4)).^(1/2)).*4-(0.85.*exp(-4)).^(1/2)+q)./(2+((0.85.*exp(-4)).^(1/2)).*4-(0.85.*exp(-4)).^(1/2)))))-1)));
f=((b.*(1-e).*(1-e).*a.*(1-k)))./(1-k).*0.50;
t=f.*(1-k);

surf(q, a, t, 'edgecolor', 'none');
xlabel('q');
ylabel('a');
zlabel('t')

[surabhi sachdeva]

Thank you sir.. Thank you so much

I got the 3 D plot

Regards