Mathematics · 2018
JEE Main · 15 April 2018, Shift 1 · Q89
An aeroplane flying at a constant speed, parallel to the horizontal ground, √ 3 km above it, is observed at an elevation of 60° from a point on the…
An aeroplane flying at a constant speed, parallel to the horizontal ground, $\displaystyle \sqrt{3} \mathrm{~km}$ above it, is observed at an elevation of $\displaystyle 60$° from a point on the ground. If, after five seconds, its elevation from the same point, is $\displaystyle 30$°, then the speed (in km/hr) of the aeroplane, is :
Official answer
(2)
$\displaystyle 1440$
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JEE Main 2018 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.