Mathematics · 2021
JEE Main · 26 August 2021, Shift 2 · Q69
A 10 inches long pencil AB with mid point C and a small eraser P are placed on the horizontal top of a table such that PC =√ 5 inches and ∠ PCB =…
A $\displaystyle 10$ inches long pencil AB with mid point C and a small eraser P are placed on the horizontal top of a table such that $\displaystyle \mathrm{PC}=\sqrt{5}$ inches and $\displaystyle \angle \mathrm{PCB}=\tan ^{-1}(2)$.
The acute angle through which the pencil must be rotated about $\displaystyle C$ so that the perpendicular distance between eraser and pencil becomes exactly $\displaystyle 1$ inch is :
Official answer
(2)
$\displaystyle \tan ^{-1}\left(\frac{3}{4}\right)$
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JEE Main 2021 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.