JEE Mains · Maths · STD 12 - 10. vector algebra
Let \(\vec{a}=3 \hat{i}+\hat{j}-\hat{k}\) and \(\overrightarrow{ c }=2 \hat{ i }-3 \hat{ j }+3 \hat{k}\). If \(\vec{b}\) is \(a\) vector such that \(\vec{a}=\vec{b} \times \vec{c}\) and \(|\vec{b}|^2=50\), then \(|72-| \vec{b}+\left.\vec{c}\right|^2 \mid\) is equal to \(..........\).
- A \(65\)
- B \(64\)
- C \(66\)
- D \(63\)
Answer & Solution
Correct Answer
(C) \(66\)
Step-by-step Solution
Detailed explanation
\(|\overrightarrow{ a }|=\sqrt{11},|\vec{c}|=\sqrt{22}\) \(|\vec{a}|=|\overrightarrow{ b } \times \overrightarrow{ c }|=|\overrightarrow{ b }||\overrightarrow{ c }| \sin \theta\) \(\sqrt{11}=\sqrt{50} \sqrt{22} \sin \theta\) \(\Rightarrow \sin \theta=\frac{1}{10}\)…
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