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JEE Main20253 Apr 2025Evening ShiftMathematicsVector AlgebraActual

Let a = i +2 j + k , b =3 i -3 j +3 k , c =2 i - j +2 k and d be a vector such that b d = c d and a d =4 . Then |( a d )|^2 is equal to ______ .

Correct answer

0

Step-by-step solution

aligned & b d = c d -and a d =4 & ~d = ( b - c )= ( i -2 j + k ) & a d =4 =-2 & Also. | a d |^2+| a d |^2=| a |^2| ~d |^2 & | a d |^2=6 4 6-16=128 aligned

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