Statics force problem - Force required to be a minimum

[Sxq]

1. Homework Statement :
If the resultant force acting on the bracket is required to be a minimum, determine the magnitude of F1.

I understand how to solve problems like this, I just don't understand what it means when it says that the force is required to be a minimum. Any help would be great!

http://img40.imageshack.us/img40/8929/staticsproblem.png

 

[nvn]

Compute the resultant force. Now try different F1 magnitudes to see if it increases or decreases the resultant force. See if something would minimize the resultant force.

 

[Sxq]

A friend said that I should take the derivative (of what?), set it to 0, and find the minimum that way. Does that make any sense?

 

[nvn]

That's right, Sxq! Of R, the resultant. R is a function of F1; i.e., R(F1). Give it a try. Hint 1: Don't forget the chain rule.

 

[Sxq]

Okay thanks!
I got it =p