If a is any vector, then |a x i|^2 + |a x j|^2 + |a x k|^2 is equal to Option 1: |a|^2 Option 2: 2|a|^2 Option 3: 3|a|^2 Option 4: 4|a|^2

The answer is '2|a|^2'. View full solution:

Algebra > Vector Algebra

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If $\vec{a}$ is any vector, then $|\vec{a} \times \hat{i}|^2 + |\vec{a} \times \hat{j}|^2 + |\vec{a} \times \hat{k}|^2$ is equal to

$|\vec{a}|^2$

$2|\vec{a}|^2$

$3|\vec{a}|^2$

$4|\vec{a}|^2$

✅ Correct Option: 2

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