If |u| = 6, |v| = 5, and the angle theta between u and v is 30 degrees, what is |u x v|?
Answer and explanation
Correct answer: C. 15
- Step 1: The magnitude of cross product is |u x v| = |u| |v| sin(theta). Step 2. |u x v| = 6 5 sin(30 deg) = 30 0.5 = 15. Answer: 15. Why not the others:* 15 root 3 uses cos(30 deg) which is the dot product magnitude; 30 omits the sine factor; 25 uses v squared.
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