Gr8shandini,---
Ok, Ok, I forgot how rough the crowd here can be
---no I'm not going to derive it---can't do good math on Pprune
but it's simply---M=CSC[mu].....mu= angular Mach come deflection simple vector math---now may I?
any book in advanced aero eng has this though---so don't accuse me of wiki/google---I like McGraw Hill
PA