∣(a−b)×(a+b)∣2+4(a⋅b)2
=∣a×a+a×b−b×a−b×b∣2+4(a⋅b)2
=4[∣a×b∣2+(a⋅b)2]=4∣a∣2∣b∣2=4×9×16=576
Let θ be the angle between the vectors a and b, where ∣a∣=4,∣b∣=3 and θ∈(4π,3π). Then ∣(a−b)×(a+b)∣2+4(a⋅b)2 is equal to ______
Held on 25 Jun 2022 · Verified 6 Jul 2026.
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