# Proving the number of leaves of a tree. (Graph Theory)

Prove that if a tree has $n$ vertices (Where $n\geq 2$)and no vertices has degree of $2$, then $T$ has at least $\frac{n+2}{2}$ leaves.

Suppose that $T$ has less than $\frac{n+2}{2}$ leaves and arrive at a contradiction. Given this fact,i deduce that $T$ has more than or equal to $n-\frac{n+2}{2}=\frac{n-2}{2}$ internal vertices.