Question

Prove: -

Answer 1

it is a mixture of dot & cross product of vectors.

Answer 2

just cmopute it out using abstract vectors


like

\[<v_1,v_2,v_3>\]

Answer 3

Isn't there a logical way?

Answer 4

yes aXb is perpendicular to both a and b

Answer 5

Let
\[ A = a_1 i + a_2 j + a_3 k \\
B = ...\]
A . A x B = |determinant of matrix of coefficients|
try it ... you will reach the conclusion

Answer 6

k! thanx I have got it:)