Question:
Compute \((2\vec i-3\vec j)\cdot(\vec i+\vec k)\).
Compute \((2\vec i-3\vec j)\cdot(\vec i+\vec k)\).
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Only same-direction pairs ($i\cdot i$, $j\cdot j$, $k\cdot k$) contribute.
Updated On: Oct 17, 2025
- \(2\)
- \(-1\)
- \(3\)
- \(0\)
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The Correct Option is A
Solution and Explanation
Write components: \((2,-3,0)\) and \((1,0,1)\).
Dot product \(=\) multiply componentwise and add:
\[
2\cdot1+(-3)\cdot0+0\cdot1=2.
\]
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