In the late 1800s, a railway engineer named Philbert Maurice d’Ocagne was part of a group of men faced with the task of expanding the French rail system. Before a single rail could be laid, the ...

To sketch the graph of a polar equation a good first step is to sketch the graph in the Cartesian coordinate system. This will give a way to visualize how r changes with θ. The information about how r ...

A set of vertices S of a connected graph G is a nonseparating independent set if S is independent and G–S is connected. The nsis number 𝒵(G) is the maximum cardinality of a nonseparating independent ...