JEE Mains · Maths · STD 12 - 10. vector algebra
If \(\left[ {a \times b\;\;b \times c\;\;c \times a} \right] = \lambda \;{\left[ {a\;\;b\;\;c} \right]^2}\) then \(\lambda\) is equal to
- A \(0\)
- B \(1\)
- C \(2\)
- D \(3\)
Answer & Solution
Correct Answer
(B) \(1\)
Step-by-step Solution
Detailed explanation
L. H.S. \(=(\bar{a} \times \bar{b}) \cdot[(\vec{b} \times \vec{c}) \times(\vec{c} \times \vec{a})]\) \(=(\vec{a} \times \vec{b}) \cdot[(\vec{b} \times \vec{c} \cdot \vec{a}) \vec{c}-(\vec{b} \times \vec{c} \cdot \vec{c}) \vec{a}]\)…
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