What is the dot product of u = (3, 1, -2) and v = (1, -1, 1)?
Answer and explanation
Correct answer: C. 0
- Step 1: u . v = x1 x2 + y1 y2 + z1 z2.
- Step 2: (3)(1) + (1)(-1) + (-2)(1) = 0.
Answer
0.
Why not the others: All three products must be added with their signs; the other values use absolute values, multiply the sums of the components, or flip one sign.
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