need a help doing simple code

Hello guys. I have some problem in below code.

First of all I want to input 4 variables(W, L, H, R).

And then q,a,b are defined as below.

q=H/L, a=W/q, b=(W*(1-R)/(2*q));

And then fuction f(X), g(X), h(x), p(x) are defined as below

f(x)=sqrt(a*x+b^2)-x-b

h(x)=W*0.9-x;

and the intersection of f(x) and h(x) is defined as (m,n)

and then g(x)=f(t)/t*x , (t,f(t)) is a point on the f(x)

p(x)=(f(t)-n)/(t-m)*(x-m)+n

now, A(t) is defined as below.

A(t)=integral of (f(x)-g(x)) at (0<x<t) + integral of (f(x)-p(x)) at (t<x<m)

and I want to show the value of t when A'(t)=0

Can you guy help me...?

Answer 1

[Thorsten]

To learn Matlab you can start by something like

 function y = myfunction(W, L, H, R)
 q=H/L;
 a=W/q; 
 b=(W*(1-R)/(2*q));

and so on and then ask more specific questions if you have further problems. I might be hard to find someone that does your homework for you, and it wouldn't help you in the long run.

[Geonhee LEE]

thank you for answering my question. As you said, I set up the functions and try to solve the integral but a error has occured.

my code :

>> syms L;

>> syms W;

>> syms a;

>> syms q;

>> syms n;

>> syms m;

>> syms R;

>> q = H./L;

a = W./q;

b = (W*(1-R)/(2*q));

m = (0.01*(81.0*W^2 + 180.0*b*W))/a;

>> n=sqrt(a*m+b^2)-m-b;

>> syms x;

>> f=sqrt(a*x+b^2)-x-b;

>> h=W*0.9-x;

>> m=(0.01*(80.1*W^2+180.0*b*W)/a);

>> n=sqrt(a*m+b^2)-m-b;

>> syms t;

>> f=@(x) sqrt(a*x+b^2)-x-b;

>> g=@(x,t) (sqrt(a*t+b^2)-t-b)/t*x;

>> p=@(x,t) ((sqrt(a*t+b^2)-t-b)-n)/(t-m)*(x-m)+n;

>> a=integral (f,0,m)-integral (g,0,t)-integral(p,t,m);

and here, I want to calculate the total integral, but some error has occured..

how do I solve it?

thank you.

[Thorsten]

I do not have the syms toolbox, so I cannot give further advice.