JEE Mains · Maths · STD 12 - 10. vector algebra
If \(\overrightarrow x = 3\hat i - 6\hat j - \hat k\) , \(\overrightarrow y = \hat i + 4\hat j - 3\hat k\) and \(\,\,\overrightarrow z = 3\hat i - 4\hat j - 12\hat k\) , then the magnitude of the projection of \(\overrightarrow x \times \overrightarrow y \) on \(\overrightarrow z\) is
- A \(12\)
- B \(15\)
- C \(14\)
- D \(13\)
Answer & Solution
Correct Answer
(C) \(14\)
Step-by-step Solution
Detailed explanation
Let \(\vec x = 3\hat i - 6\hat j - \hat k,\vec y = \hat i + 4\hat j - 3\hat k\) and \(\vec z = 3\hat i - 4\hat j - 12\hat k\) Now, \(\vec x \times \vec y = \begin{array}{*{20}{c}} {\hat i}&{\hat j}&{\hat k}\\ 3&{ - 6}&{ - 1}\\ 1&4&{ - 3} \end{array}\)…
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