Show that each of the following triads of vectors is coplanar :

Formula : -


and then,



(iii) Three vectors are coplanar if and only if a.(b×c) = 0


Given: -



we know that three vector a,b,c are coplanar if their scalar triple product is zero



we have



now, using



= 1(15 – 12) + 2( – 10 + 4) + 3(6 – 3)


= 3 – 12 + 9 = 0


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