JEE Mains · Maths · STD 12 - 10. vector algebra
Let \(\vec{a}=6 \hat{i}+\hat{j}-\hat{k}\) and \(\vec{b}=\hat{i}+\hat{j}\). If \(\vec{c}\) is a is vector such that \(|\vec{c}| \geq 6, \vec{a} \cdot \vec{c}=6|\vec{c}|,|\vec{c}-\vec{a}|=2 \sqrt{2}\) and the angle between \(\vec{a} \times \vec{b}\) and \(\vec{c}\) is \(60^{\circ}\), then \(|(\vec{a} \times \vec{b}) \times \vec{c}|\) is equal to :
- A \(\frac{9}{2}(6-\sqrt{6})\)
- B \(\frac{3}{2} \sqrt{3}\)
- C \(\frac{3}{2} \sqrt{6}\)
- D \(\frac{9}{2}(6+\sqrt{6})\)
Answer & Solution
Correct Answer
(D) \(\frac{9}{2}(6+\sqrt{6})\)
Step-by-step Solution
Detailed explanation
\( |(\overrightarrow{\mathrm{a}} \times \overrightarrow{\mathrm{b}} \times \overrightarrow{\mathrm{c}})|=|\overrightarrow{\mathrm{a}} \times \overrightarrow{\mathrm{b}}||\overrightarrow{\mathrm{c}}| \frac{\sqrt{3}}{2} \) \( |\overrightarrow{c}-\overrightarrow{a}|=2 \sqrt{2} \)…
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