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GUJCET · Maths · Vector Algebra
It \(|\vec{a}|=3\), then, the value of \(|\vec{a} \times \hat{i}|^2+|\vec{a} \times \hat{j}|^2+|\vec{a} \times \hat{k}|^2\) is _________ .
- A 27
- B 9
- C 18
- D 36
Answer & Solution
Correct Answer
(C) 18
Step-by-step Solution
Detailed explanation
\(|\vec{a} \times \hat{i}|^2+|\vec{a} \times \hat{j}|^2+|\vec{a} \times \hat{k}|^2 = 2|\vec{a}|^2\) \( = 2(3)^2\)
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