Ski Track for Ski Jump
In order to prepare for the Winter Olympics
games, a ski resort is checking its slopes to make sure that they are
compatible with Olympics standard. One of the ski tracks for the ski
jump can be described using the function r = 100cos2θ meters
for 0 ≤ θ ≤ π/2,
as shown in the figure. The organizers of the games would like to find
out what is the total length of the ski track.