∣c−a∣=∣c∣2+∣a∣2−2a⋅c=∣c∣2+4−0∵a=b×c∣a∣=∣b×c∣2=3∣c∣sinα∣c∣=32cosecαα∈[0,3π]∣c∣min=32×32cosecα∈[32,∞)⇒27∣c−a∣min2=27(2716+4)=124
JEE Main 2024 — Mathematics Vectors & 3D Geometry
Consider three vectors a,b,c. Let ∣a∣=2,∣b∣=3 and a=b×c. If α∈[0,3π] is the angle between the vectors b and c, then the minimum value of 27∣c−a∣2 is equal to:
Held on 5 Apr 2024 · Verified 6 Jul 2026.
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