Doug Ensley

Professor of Mathematics

Shippensburg University

Discrete Math

Errata list

On page 50, in the solution to Practice Problem 7b the negation is given correctly but it is the original statement, not the negation, that is the true statement.

In Problem 21 of Section 2.6, the second card shown should have a "19" in place of one of the two "3"s that errantly appear on that card.

For Problem #3(d) in Section 3.3, the "equality" symbol should be replaced with the "subset" symbol to create a true statement that can be proved.

On page 271, in Figure 4-26, g is not a function (3 relates to both 2 and 4). The arrow 3-->4 should be 4-->3.

For Problem #21 in Section 6.2, the answers in the back of the book and in the Student Solution Manual are incorrect. The correct answer for part (a) is 4^3/C(50,3), and the correct answer for part (c) is 4^4/C(50,3)

On page 519, the assumption of "simple" in the hypothesis is not needed. Proposition 2 and 3 characterize all connected graphs, not just the simple ones.

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Doug Ensley
Department of Mathematics
Shippensburg University

Shippensburg, PA 17257

Phone: (717) 477-1477
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