JEE Main2012MathematicsVector AlgebraActual

If a = i -2 j +3 k , b =2 i +3 j - k and c = i + j +(2 -1 k ) are coplanar vectors, then is equal to

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Step-by-step solution

Since a = i -2 j +3 k , b =2 i +3 j - k and c = i + j +(2 -1 k ) are coplanar therefore [ a b c ]=0 aligned & i.e., | array ccc 1 & 2 & -2 & 3 & 1 3 & -1 & 2 -1 array |=0 & 1(6 -2)-2(-4 -1)+ (-7)=0 & (6 -2)+8 +2+2+2 -9 =0 & 7 =0 =0 aligned

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