What is the dot product of and ?
Answer and explanation
Correct answer: B. -21
- Step 1: Recall the definition of the vector dot product: .
- Step 2: Calculate each component product for and .
- Step 3: Combining the terms produces .
Answer
-21.
Why not the others: 21 reverses the sign of the scalar dot product; 9 is an overestimation arithmetic miscalculation; -25 is an underestimation arithmetic miscalculation.
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