Question:
\(\big(3\vec{i}-4\vec{k}\big)^{2}=\) ?
\(\big(3\vec{i}-4\vec{k}\big)^{2}=\) ?
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\(\|\mathbf{v}\|^{2}=\mathbf{v}\cdot\mathbf{v}\).
Updated On: Oct 17, 2025
- \(1\)
- \(25\)
- \(7\)
- \(49\)
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The Correct Option is B
Solution and Explanation
Here "square" means dotting the vector with itself (magnitude squared):
\[
(3\vec{i}-4\vec{k})\cdot(3\vec{i}-4\vec{k})=3^{2}+(-4)^{2}=9+16=25.
\]
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