Exams › JEE Advanced › Maths
Let |a| = 2, |b| = 1, |c| = 3. The angle between a and b is pi/3, between b and c is pi/4, and between c and a is pi/2. If |a - 2b + c| can be expressed as sqrt(p + q*sqrt(2)) where p, q are integers, find (p + q).
- 8
- 10
- 12
- 6
Correct answer: 10
Solution
Expand |a - 2b + c|², substitute all dot products, then simplify to identify p and q.
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