In: Advanced Math
A tree is a circuit-free connected graph. A leaf is a vertex of degree 1 in a tree. Show that every tree T = (V, E) has the following properties: (a) There is a unique path between every pair of vertices. (b) Adding any edge creates a cycle. (c) Removing any edge disconnects the graph. (d) Every tree with at least two vertices has at least two leaves. (e) | V |=| E | +1.