I am currently stuck on a digital systems homework question. We are given a custom logic gate with a truth table (its effectively an AND gate where one of the inputs have a NOT gate). With this logic gate and truth table, we are told that we can build any combinational logic function and we have to show this by building 2-input AND gates, 2-input OR gates, and a NOT gate from the custom logic gate and truth table given (Figure 1).

*Figure 1 - The custom logic gate, and truth table.*

I have figured out how to build the 2-input AND gate (Figure 2), although I have no idea where to start on building the 2-input OR gate and the NOT gate. I spent 2 hours trying to figure out how to build the OR gate but couldn't figure it out! And I was stumped as to how you would build a NOT gate as it only has one input, and if the input is 0, the output would always be 0 no matter how many of these custom logic gates you had, and the way you had them circuited. I had no clue how you could turn the 0 input into a 1 by these logic gates??

*Figure 2 - The 2-input AND gate I built from the custom logic gates.*

Thanks!