Dear John, Thanks for the good work. Please help me distinguish the use of these two curves (of TC Vs TR) in explaining the profit maximising output. So i have simply attached the links.
You will never be asked to draw any graphs relating to this.
All you will need to do is to be aware that profit is maximised when marginal revenue is equal to marginal cost.
If you watch my lecture you will see that I use the total revenue and total cost curves to explain why this is the case, but again you will never be asked to draw them.