Hi, well got my exam tomorrow and this is the only topic area I struggle with soo much, a past paper i'm trying here asks this qustion:
It is given that
Use the formulae for and to show that .
I know that I treat the +1 as n but I really dont know where I should take out factors or when I should expand etc. Also I get the formulas for the r squared and r so im aware of what they are.
Each time Ive tried Ive managed to get to either or
I would be really greatful if someone could explain what process I should do to get the answer.