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NDA 2012
Exam
NDA
Year
2012
Subject
Mathematics
Chapter
Vector Algebra

NDA 2012 · Mathematics · Vector Algebra

If a =(2,1,-1), b =(1,-1,0), c =(5,-1,1) , then wha is the unit...

If a⃗=(2,1,−1),b⃗=(1,−1,0),c⃗=(5,−1,1)\vec{a}=(2,1,-1), \vec{b}=(1,-1,0), \vec{c}=(5,-1,1), then wha is the unit vector parallel to a⃗+b⃗−c⃗\vec{a}+\vec{b}-\vec{c} in the opposite direction?

Options

  1. Ai^+j^−2k^3\frac{\hat{i}+\hat{j}-2 \hat{k}}{3}
  2. Bi^−2j^+2k^3\frac{\hat{i}-2 \hat{j}+2 \hat{k}}{3}
  3. C2i^−j^+2k^3\frac{2 \hat{i}-\hat{j}+2 \hat{k}}{3}
  4. DNone of the above

Correct answer

C. 2i^−j^+2k^3\frac{2 \hat{i}-\hat{j}+2 \hat{k}}{3}

Step-by-step solution

The correct answer is option C.
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