CSCI 250 Spring 2013Discrete Structures Archived Class

# Homework 4

• Problems are taken from the textbook unless otherwise noted.
• For full credit, provide context for each problem, show all calculations, and justify all answers by providing enough comments to explain your reasoning.
• You will lose a significant amount of credit if you do not provide context, calculations, and justifications for a problem.
• Numbers and/or algebra by themselves are not enough. A correct answer with no justification will be worth no more than half credit, and sometimes much less than that.
• Precision is very important. You cannot skip steps, make guesses, or use flawed logic. Any of these things can lead to incorrect answers.
• Homework assignments must be very neatly written or typeset (e.g. using Word or OpenOffice).
• You must indicate any assistance/collaboration you had on an assignment as specified on the Policies page.

## Details

SectionProblemNotes
1.616bcClearly state whether or not the argument is correct and give the specific rule(s) of inference or fallacy used.
20Explain why or why not, specifying rules of inference/fallacies.
1.72Be very precise, using the definition of even. You cannot not say, for instance, that 10x+14y-6z+12 is even. You must use algebra to make it look like 2k for some integer k. Similarly for future problems dealing with with either odd or even numbers. Also, a common mistake on this kind of proof is to write it in such a way that you are essentially assuming the two numbers are the same number without realizing it.
18Take the assumption that n is an integer as a given, and read the problem as "If 3n+2 is even, then n is even."
24