1) A body slides down a logarithmic slide due to gravity. Its coordinates (x, y) belong to the graph of the function f(x) = 1/2 log(x) + 4. It starts from rest at point A and reaches the ground at point B. 2) The intersections of the graph of the function f(x) = m/x^n - 2 with the axes are analyzed for different values of m and n. 3) The lengths of successive similar triangles constructed from an equilateral triangle are shown to form a geometric progression.