It is a formula for finding any power of a binomial without multiplying at length.
for ex ifyou have to find the expansion of {x+y}^n then we will use binomial expansion. 
If u don't find this than plz ans my another question. WHT CGPA I GET IN X, ............. I M POSTED ALREADY
They are calculated by your FA tests
I knw that but hw to calculate
Listen I m posted all my grades in that question plz can u tell my CGPA
Sorry i know only this