[Oops.] Bugs in Approximation Chapter J.9

[reteps]

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Chapter number or note title: J.8

Page number: 11

Error description: typo

Pushing this idea to its limits us the following negative result.

Suggested fix (if any):

Pushing this idea to its limits gives us the following negative result.

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Chapter number or note title: J.8

Page number: 12

Error description: typo

Suggested fix (if any):

Swap (3) and (4) in the left graph

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Chapter number or note title: J.8

Page number: 12

Error description: bug in proof

On the other hand, if we remove any edge from the optimal tour, we obtain
a spanning tree (in fact a spanning path) of the graph; thus, MST ≥ OPT.

Suggested fix (if any):

MST <= OPT.