When applying KCL at the node for the first equation, why doyou choose the current (io) to have a positive sign?I.e. how do you know that current is flowing into the node?
When working out the power dissipated you have the equationusing the same current (io) but this time you use anegative sign in the equation.
How do you know when to use a positive or negative sign for this current in both situations?