Question:
If ( a × b)² + ( a · b)² = 676 and | b| = 2, then | a| is equal to
If ( a × b)² + ( a · b)² = 676 and | b| = 2, then | a| is equal to
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Use vector identity to avoid lengthy calculations.
Updated On: Mar 18, 2026
- 13
- 26
- 39
- None of these
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Verified By Collegedunia
The Correct Option is A
Solution and Explanation
Step 1: Identity: ( a × b)² + ( a · b)² = a² b²
Step 2: a²(2)² = 676 a² = 169
Step 3: | a| = 13
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