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Paragraph: Let Q be the image of the point P (-2,1,-5) in the plane 3 x-2 y+2 z+1=0 . Question: Consider the following: 1. The direction ratios of the line segment PQ are 3,-2,2 . 2. The sum of the squares of direction cosines of the line segment PQ is unity. Which of the above statements is/are correct?

Options

  1. A1 only
  2. B2 only
  3. CBoth1 and 2
  4. DNeither 1 nor 2

Correct answer

C. Both1 and 2

Step-by-step solution

From (i) above, 1 is correct. We know that, Sum of direction cosines of the line segment PQ =1 .

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