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NDA 2012
Exam
NDA
Year
2012
Subject
Mathematics
Chapter
Vector Algebra

NDA 2012 · Mathematics · Vector Algebra

If the magnitudes of two vectors a and b are equal then which one...

If the magnitudes of two vectors a⃗\vec{a} and b⃗\vec{b} are equal then which one of the following is correct?

Options

  1. A(a⃗+b⃗)(\vec{a}+\vec{b}) is parallel to (a⃗−b⃗)(\vec{a}-\vec{b})
  2. B(a⃗+b⃗)∙(a⃗−b⃗)=1(\vec{a}+\vec{b}) \bullet(\vec{a}-\vec{b})=1
  3. C(a⃗+b⃗)(\vec{a}+\vec{b}) is perpendicular to (a⃗−b⃗)(\vec{a}-\vec{b})
  4. DNone of the above

Correct answer

C. (a⃗+b⃗)(\vec{a}+\vec{b}) is perpendicular to (a⃗−b⃗)(\vec{a}-\vec{b})

Step-by-step solution

The correct answer is option C.
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