Coordinate Geometry · NDA previous year questions

2017 27 questions

1. Q952017 · 23 Apr 2017

   If $\vec{a}\times \vec{b}=\vec{c}$ and $\vec{b}\times \vec{c}=\vec{a}$, then which one of the following is correct?

   1. A.$\vec{a},\vec{b},\vec{c}$ are orthogonal in pairs and $|\vec{a}|=|\vec{c}|$ and $|\vec{b}|=1$
   2. B.$\vec{a},\vec{b},\vec{c}$ are non-orthogonal to each other
   3. C.$\vec{a},\vec{b},\vec{c}$ are orthogonal in pairs but $|\vec{a}|\ne |\vec{c}|$
   4. D.$\vec{a},\vec{b},\vec{c}$ are orthogonal in pairs but $|\vec{b}|\ne 1$
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   Answer: A

2. Q962017 · 23 Apr 2017

   If $\vec{a}=2\hat{i}+3\hat{j}+4\hat{k}$ and $\vec{b}=3\hat{i}+2\hat{j}-\lambda \hat{k}$ are perpendicular, then what is the value of $\lambda$?

   1. A.2
   2. B.3
   3. C.4
   4. D.5
   Show answer

   Answer: B