Problem Statement: If the resultant force acting on the bracket is required to be a minimum, determine the magnitude of F1 and the resultant force. Set ∅=30 deg. I have found the components of each force and set them up into a resultant vector, with F1 solved symbolically into its components. I'm not sure how to find the magnitude of F1 so that the resultant is a minimum. Also, what is the significance of the 'u' axis? I understand I have to take the derivative of the resultant but I'm not sure how its done. Any help is appreciated, Thanks!