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5.6: Trees

  • Page ID
    88873
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    Terminology

    Definition \(\PageIndex{1}\): Tree

    A graph is a tree if and only if it is connected and contains no cycles.

    Definition \(\PageIndex{2}\): Leaf

    A vertex in a tree is a leaf if and only if it has degree one.

    Definition \(\PageIndex{3}\): Spanning Tree.

    A graph \(G\) is a spanning tree of a graph \(H\) if and only if \(G\) is a subgraph of HH that contains all the vertices of \(H\) and is a tree.

    Practice

    Checkpoint \(\PageIndex{4}\)

    Determine which graphs in Figure Figure 5.1.1 are trees.

    Checkpoint \(\PageIndex{4}\)

    Draw all non-isomorphic trees on 3 vertices.

    Checkpoint \(\PageIndex{4}\)

    Prove that every tree with at least two vertices has at least one leaf.

    Checkpoint \(\PageIndex{4}\)

    Draw a tree with 7 vertices. Determine for what \(n\) the tree is \(n\)-connected.

    Checkpoint \(\PageIndex{4}\)

    Explain why for any tree removal of a leaf produces another tree.

    Checkpoint \(\PageIndex{4}\)

    Find a spanning tree for every graph in Figure 5.2.43.


    This page titled 5.6: Trees is shared under a GNU Free Documentation License 1.3 license and was authored, remixed, and/or curated by Mark A. Fitch via source content that was edited to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.

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