4.86. Evaluate the proposed proof of the following result. Result Let x, y E Z such that 3|x. If 3|(x +y), then 3 y. Proof Since 3x, it follows that a = 3a, where a E Z. Assume that 3 (x + y). Then x+y = 3b for some integer b. Hence, y = 36 – x = 3b – 3a = 3(b – a). Since b- a is an integer, 3 y. For the converse, assume that 3 y. Therefore, y = 3c, where c€ Z. Thus, x +y = 3a + 3c = 3(a + c). Since a + c is an integer, 3 (x +y).

Advanced Engineering Mathematics
10th Edition
ISBN:9780470458365
Author:Erwin Kreyszig
Publisher:Erwin Kreyszig
Chapter2: Second-order Linear Odes
Section: Chapter Questions
Problem 1RQ
icon
Related questions
Topic Video
Question

Any mistake in the proof or corrections needed to be made

4.86. Evaluate the proposed proof of the following result.
Result Let x, y € Z such that 3 x. If 3 (x + y), then 3 y.
Proof Since 3 x, it follows that x =
у — 36 — ӕ — 3b — За — 3(b — а).
Since b – a is an integer, 3|y.
For the converse, assume that 3|y. Therefore, y = 3c, where c € Z. Thus, x + y = 3a + 3c = 3(a + c). Since a + c is an
integer, 3|(x + y).
3a, where a E Z. Assume that 3|(x + y). Then x + y = 3b for some integer b. Hence,
Transcribed Image Text:4.86. Evaluate the proposed proof of the following result. Result Let x, y € Z such that 3 x. If 3 (x + y), then 3 y. Proof Since 3 x, it follows that x = у — 36 — ӕ — 3b — За — 3(b — а). Since b – a is an integer, 3|y. For the converse, assume that 3|y. Therefore, y = 3c, where c € Z. Thus, x + y = 3a + 3c = 3(a + c). Since a + c is an integer, 3|(x + y). 3a, where a E Z. Assume that 3|(x + y). Then x + y = 3b for some integer b. Hence,
Expert Solution
Given conditions.

We have to check the proof for it's correction.

steps

Step by step

Solved in 2 steps

Blurred answer
Knowledge Booster
Propositional Calculus
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, advanced-math and related others by exploring similar questions and additional content below.
Similar questions
Recommended textbooks for you
Advanced Engineering Mathematics
Advanced Engineering Mathematics
Advanced Math
ISBN:
9780470458365
Author:
Erwin Kreyszig
Publisher:
Wiley, John & Sons, Incorporated
Numerical Methods for Engineers
Numerical Methods for Engineers
Advanced Math
ISBN:
9780073397924
Author:
Steven C. Chapra Dr., Raymond P. Canale
Publisher:
McGraw-Hill Education
Introductory Mathematics for Engineering Applicat…
Introductory Mathematics for Engineering Applicat…
Advanced Math
ISBN:
9781118141809
Author:
Nathan Klingbeil
Publisher:
WILEY
Mathematics For Machine Technology
Mathematics For Machine Technology
Advanced Math
ISBN:
9781337798310
Author:
Peterson, John.
Publisher:
Cengage Learning,
Basic Technical Mathematics
Basic Technical Mathematics
Advanced Math
ISBN:
9780134437705
Author:
Washington
Publisher:
PEARSON
Topology
Topology
Advanced Math
ISBN:
9780134689517
Author:
Munkres, James R.
Publisher:
Pearson,