1. The problem statement, all variables and given/known data Using symbols, write PRL, the power dissipated in RL as a function of RL (your other symbols are R0 and the power supply voltage epsilon both of which are constant. 10V and 100ohms) and then take the derivative of this function with respect to RL for which PRL has an extreme value, in this case a maximum. 2. Relevant equations V = IR 3. The attempt at a solution So here's what I was thinking... PRL = VI where I = V/R so replace that with Epsilon2/R0 Then plug in the constant values 10V and 100ohms to get PRL = 1W dRL Not sure where to go from here though as the derivative gives zero. What am I missing? Did I do it all incorrectly? Thanks in advance!