Question:
\((11\vec{i}-7\vec{j}-\vec{k})\cdot(8\vec{i}-\vec{j}-5\vec{k})=\) ?
\((11\vec{i}-7\vec{j}-\vec{k})\cdot(8\vec{i}-\vec{j}-5\vec{k})=\) ?
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Dot product is distributive and commutative for componentwise multiplication and addition.
Updated On: Oct 17, 2025
- \(95\)
- \(100\)
- \(400\)
- \(88\)
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The Correct Option is B
Solution and Explanation
Compute componentwise:
\[
11\cdot 8+(-7)\cdot(-1)+(-1)\cdot(-5)=88+7+5=100.
\]
So the dot product equals \(100\).
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