If two non-zero vectors a and b satisfy a . b = 0, what is the angle between them?
Answer and explanation
Correct answer: D. 90 degrees
- Step 1: The dot product is given by |a| |b| cos(theta) = 0. Step 2. Since vectors are non-zero, cos(theta) = 0, which gives theta = 90 degrees. Answer: 90 degrees. Why not the others: 0 degrees represents parallel vectors; 180 degrees represents antiparallel vectors; 45 degrees yields a dot product of |a||b|/sqrt(2).
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