SIR,

PLEASE help me to understand the second video in the videos given by the teachers

easy toh hai....just listen carefully!

 so simple just concentrate more.good luck

just understand by listening to it carefully and recalling the axioms as taught before........

see it's just easy.Just concentrate. Its also in one of the examples in text book.You may refer it...

listen keep a pen and a paper side by side and do it what ma'am explains