All quadratic functions have the same type of curved graphs with a line of symmetry. The graph of the quadratic function y = a x 2 + b x + c is a smooth curve with one turning point.

Learn how to use functions to represent translations, sketches, compressions and reflections of graphs with GCSE Bitesize Maths.

Ivan Baggs, Functions with a Closed Graph, Proceedings of the American Mathematical Society, Vol. 43, No. 2 (Apr., 1974), pp. 439-442 ...