Find the dot product of the vectors a = (1, -3) and b = (5, 2).
Answer and explanation
Correct answer: A. -1
- Step 1: The dot product is a.b = x1 x2 + y1 y2.
- Step 2: a.b = (1)(5) + (-3)(2) = -1.
Answer
-1.
Why not the others: '-13' cross-multiplies the components; '11' subtracts the second product; '17' gives the 2D cross product.
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