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Manipal MET2016MathematicsVector Algebra

If a and b be two perpendicular unit vectors such that x = b +( a x ) , then | x | is equal to

Options

  1. A1
  2. B1 2
  3. C2
  4. D3

Correct answer

C. 2

Step-by-step solution

We have, a x =0 Also, x = b +( x a ) array ll & x a = b a +( x a ) a & x a = b a +( x a ) a -( a a ) x & x - b = b a - x array |2 x |=| b + b a | | x |= 1 2

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