2. Suppose ne Z. If n² is odd, then n is odd. IC-2062 96) in

Elements Of Modern Algebra
8th Edition
ISBN:9781285463230
Author:Gilbert, Linda, Jimmie
Publisher:Gilbert, Linda, Jimmie
Chapter2: The Integers
Section2.2: Mathematical Induction
Problem 49E: Show that if the statement is assumed to be true for , then it can be proved to be true for . Is...
icon
Related questions
Question

SUBJECT: DISCRETE MATH 

 

ANSWER #2 ONLY

Use the method of contrapositive proof to prove the following statements. (In
each case you should also think about how a direct proof would work. You will
find in most cases that contrapositive is easier.)
1. Suppose n € Z. If n² is even, then n is even.
2. Suppose n e Z. If n² is odd, then n is odd.
3. Suppose a,b € Z. If a²(b²-2b) is odd, then a and b are odd.
4. Suppose a,b,c € Z. If a does not divide be, then a does not divide b.
5. Suppose x € R. If x² +5x<0 then x < 0.
6. Suppose x E R. If x-x>0 then x>-1.
7. Suppose a, b € Z. If both ab and a+b are even, then both a and b are even.
8. Suppose x € R. If x5-4x²+3x³-x²+3x-4≥0, then x≥0.
9. Suppose n € Z. If 3+n², then 3 n.
10. Suppose x,y,ze Z and x 0. If xyz, then xy and xtz.
Transcribed Image Text:Use the method of contrapositive proof to prove the following statements. (In each case you should also think about how a direct proof would work. You will find in most cases that contrapositive is easier.) 1. Suppose n € Z. If n² is even, then n is even. 2. Suppose n e Z. If n² is odd, then n is odd. 3. Suppose a,b € Z. If a²(b²-2b) is odd, then a and b are odd. 4. Suppose a,b,c € Z. If a does not divide be, then a does not divide b. 5. Suppose x € R. If x² +5x<0 then x < 0. 6. Suppose x E R. If x-x>0 then x>-1. 7. Suppose a, b € Z. If both ab and a+b are even, then both a and b are even. 8. Suppose x € R. If x5-4x²+3x³-x²+3x-4≥0, then x≥0. 9. Suppose n € Z. If 3+n², then 3 n. 10. Suppose x,y,ze Z and x 0. If xyz, then xy and xtz.
Expert Solution
steps

Step by step

Solved in 3 steps with 3 images

Blurred answer
Recommended textbooks for you
Elements Of Modern Algebra
Elements Of Modern Algebra
Algebra
ISBN:
9781285463230
Author:
Gilbert, Linda, Jimmie
Publisher:
Cengage Learning,
Algebra: Structure And Method, Book 1
Algebra: Structure And Method, Book 1
Algebra
ISBN:
9780395977224
Author:
Richard G. Brown, Mary P. Dolciani, Robert H. Sorgenfrey, William L. Cole
Publisher:
McDougal Littell
Elementary Linear Algebra (MindTap Course List)
Elementary Linear Algebra (MindTap Course List)
Algebra
ISBN:
9781305658004
Author:
Ron Larson
Publisher:
Cengage Learning