Question:
\((\vec{i}-\vec{j}+\vec{k})\cdot(7\vec{i}-8\vec{j}+9\vec{k})=\) ?
\((\vec{i}-\vec{j}+\vec{k})\cdot(7\vec{i}-8\vec{j}+9\vec{k})=\) ?
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Write vectors as triples and use \(a_1a_2+b_1b_2+c_1c_2\).
Updated On: Oct 17, 2025
- \(22\)
- \(23\)
- \(24\)
- \(25\)
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The Correct Option is C
Solution and Explanation
Dot product: multiply components and add:
\[
1\cdot7+(-1)\cdot(-8)+1\cdot9=7+8+9=24.
\]
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