Prove that `[[bar a xx bar p, bar b xx bar p, bar cxx bar r]]+[[bar axx bar q, bar b xx bar r, bar c xx bar p]]+[[bar a xx bar r, bar b xx bar p,bar c xx bar q]]=0`

if bar a+2 bar b+3bar c=bar 0 then bar axxbar b+bar b xx bar c+bar cxx bara = lambda (bar b xx bar c) ,where lambda=

bar a, bar b, bar c are three vectros, then prove that: (bar a xx bar b) xx bar c = (bar a. bar c) bar b-(bar b. bar c) bar a.

If bar a = 2 bar I + bar j - bar k, bar b = - bari + 2 bar j - 4 bar k and bar c = bar I + bar j + bar k , then find ( bar a xx bar b) cdot (bar b xx bar c) .

If bar r=l(bar b xx bar c)+m(bar c xx bar a)+n(bar a xx bar b) and [bar a bar b bar c]=2 , then l+m+n is equal to

Compute bar(a) xx (bar(b) + bar(c )) + bar(b) xx (bar(c ) +bar(a)) + bar(c ) xx (bar(a)+bar(b))

Let bar a = 2bar i + bar k,bar b=bar i+bar j+bar k and bar c=4 bar i-3bar j+7 bar k three vectors. The vector which satisfies bar r xx bar b=bar c xx bar b and bar r.bar a=0 is