Question
There are two angles of projection for which horizontal range is same. Prove that the sum of maximum heights for these two angles is independent of angle of projection.
Solution
Given, horizontal range is same for two angles of projection.
The angles are θ and 90°–θ.
Maximum height H1 for angle projection θ is,
Maximum height H2 for angle projection 90°–θ is,
Now, sum of maximum height is,
Hence the result.