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AP EAMCET20227 Jul 2022Evening ShiftMathematicsVector AlgebraActual

a , b are two vectors such that | a |= 3 ,| b |= 2 . If x is unit vector satisfying x a = b , then x =

Options

  1. A1 2 [(x a) a-b a]
  2. B1 2 [ (x a) a+(b a)]
  3. C1 2 [(x a) a+b a]
  4. D-8 i -12 i +24 k

Correct answer

D. -8 i -12 i +24 k

Step-by-step solution

aligned & a ( x a )= a b & ( a a ) x -( a x ) a = a b [ | a |= 3 ,| a |^2=3 ] & 3 x = a b +( a x ) a & 3 x = a b ( 3 1 3 ) a & x = 1 3 ( a b a ) & | a x |=| b | & 3 1 = 2 & = 2 3 & = 1 3 aligned

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