the sum of a constant n times is n times that constant...
Theorem : Is S^2 is the variance of a random sample from a infinite population with the finite variance \sigma^2 , then E(S^2) = \sigma^2
Proof:
..............Understood!!!!
.............Understood!!!!
...................Understood!!!!
since and it follows that
...............Understood!!!!
....................Couldnt Understood!!!!
How did he get