
AG=10i^+hj^+10k^
BH=−10i^+hj^+10k^
cosθ=(200+h2)2−100+h2+100
51=200+h2h2
200=4h2
h2=50
⇒h=52
JEE Main 2021 — Mathematics Vectors & 3D Geometry
A hall has a square floor of dimension 10m×10m (see the figure) and vertical walls. If the angle GPH between the diagonals AG and BH is cos−151, then the height of the hall (in meters) is:

Held on 26 Aug 2021 · Verified 6 Jul 2026.
52
53
510
5
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