MathDB
RIP Atlantis

Source: ICMC 2023 Round 2 P1

March 1, 2023
ICMCalgebracollege contestsabsolute value

Problem Statement

The city of Atlantis is built on an island represented by [1,1][ -1, 1], with skyline initially given by f(x)=1xf(x) = 1 - |x| . The sea level is currently y=0y=0, but due to global warming, it is rising at a rate of 0.010.01 a year. For any position 1<x<1-1 < x < 1, while the building at xx is not completely submerged, then it is instantaneously being built upward at a rate of rr per year, where rr is the distance (along the xx-axis) from this building to the nearest completely submerged building. How long will it be until Atlantis becomes completely submerged?
Proposed by Ethan Tan