Solving the equation via matlab

Hi Everybody

I am trying to solve the equation in picture below but I face many problems, Is there anyone can help me.

Thanks in advance

[John D'Errico]

OK, so you have done nothing, tried nothing, and expect a solution for your homework problem. You SAY that you have faced many problems, but we see no hint.

I'll give you a suggestion. Pick values of d and L. (Use nested loops on d and L, but there are other ways.) Then solve.

[Walter Roberson]

If you let x have a vector value, then 1-exp(a*x) has a vector result. When you have a vector expression, you can use prod() to multiply all of the members of the vector together. Now you can construct an anonymous function f = @(R) 1 - prod(....) that given a particular R value calculates the right hand side of your expression. After that it is a matter of finding a numeric solution:

http://www.mathworks.com/matlabcentral/answers/103169-how-do-i-find-all-the-zeros-of-a-function