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MHT CET202019 Oct 2020Evening ShiftMathematicsVector AlgebraActual

If a , b , c are non-coplanar vectors and p = b c [ a b c ] , q = c a [a b c] , r = a b [ a b c ] , then a p + b q + c r =

Options

  1. A2
  2. B1
  3. C0
  4. D3

Correct answer

D. 3

Step-by-step solution

(C) Given that, p = b c [ array ccc a & b & c array ] , q = c a [ array ccc a & b & c array ], r = a b [ array lll a & b & c array ] a p = a ( b c ) [ array lll a & b & c array ] =1 ...(1) Similarly, b q = b ( c a ) [ a b c ] =1 ...(2) and c r = ( a b ) [ array ccc a & b & c array ] =1 ..(3) a p + b q + c r =1+1+1=3 [ from (1),(2) &(3)]

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