if `|bar a|=2,|bar b|=4` then `(|bar a xx bar b|^2)/(1-cos^2(bar a,bar b))=`

If |bar(a)|=2,|bar(b)|=4 then (|bar(a)xxbar(b)|^(2))/(1-cos^(2)(bar(a),bar(b)))=

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 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=

In Delta PQR ,let bar(QR)=bar(a),bar(RP)=bar(b) and bar(PQ)=bar(c) . If |bar(a)|=3,|bar(b)|=4 and (bar(a)*(bar(c)-bar(b)))/(bar(c)*(bar(a)-bar(b)))=(|bar(a)|)/(|bar(a)|+|bar(b)|), then the value of |bar(a)timesbar(b)|^(2) is equal to

If bar(a) = 2bar(i) - 3bar(j) + bar(k) and bar(b) = bar(i) + 4bar(j) -2bar(k) , then find (bar(a) + bar(b))xx(bar(a)-bar(b))

If |bar(a)|=1,|bar(b)|=2 , (bar(a),bar(b))=(2 pi)/(3) then |(bar(a)+3bar(b))times(3bar(a)-bar(b))|^(7)= ...

(d) answer ANY one question :1. bar a, bar b and bar c be three vectors such that bar a +bar b+ bar c =0 and |bar a|=1, |bar b|=4,|bar c |=2 . Evlautae bar a.bar b + bar b.bar c+bar c.bar a .

If bar(a)= 2bar(i) - 3bar(j) + 5bar(k), bar(b)= - bar(i) + 4bar(j)+ 2bar(k) then find (bar(a) + bar(b)) xx (bar(a) - bar(b)) and unit vector perpendicular to both bar(a) + bar(b) " & " bar(a)- bar(b) .

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