AP EAMCET · Maths · Three Dimensional Geometry
The magnitude of the projection of the vector \(\mathbf{a}=4 \mathbf{i}-3 \mathbf{j}+2 \mathbf{k}\) on the line which makes equal angles with the coordinate axes is
- A \(\sqrt{2}\)
- B \(\sqrt{3}\)
- C \(\frac{1}{\sqrt{3}}\)
- D \(\frac{1}{\sqrt{2}}\)
Answer & Solution
Correct Answer
(B) \(\sqrt{3}\)
Step-by-step Solution
Detailed explanation
Let the vector \(\mathbf{v}\) make an angle \(\alpha\) with each of the three axes, then direction cosine of \(\mathbf{v}\) are \( \) Also, \(\quad \cos ^2 \alpha+\cos ^2 \alpha+\cos ^2 \alpha=1\) Hence, direction cosine of \(\mathbf{v}\) are \( \) or \( \) So, the required line…
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