What is the magnitude of the 3D vector v = <2, -3, 6>?
Answer and explanation
Correct answer: D. 7
- Step 1: Use magnitude formula: ||v|| = sqrt(x^2 + y^2 + z^2).
- Step 2: Compute squares: 2^2 + (-3)^2 + 6^2 = 4 + 9 + 36 = 49.
- Step 3: Take square root: sqrt(49) = 7.
Answer
7.
Why not the others: '11' adds absolute values 2 + 3 + 6; 'sqrt(11)' squares 2 and -3 but drops 6^2; '49' gives ||v||^2 instead of ||v||.
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