4. Explain what is wrong in the following "proof." CLAIM. Let x be a real number. If a is irrational, then 2x is irrational. "PROOF." Take r = V2. Then r is irrational, and so is 2x = 2/2. Therefore 2x is irrational for any irrational number c. (Note. Find the mistakes in logical reasoning. "Lacks detail" is not a mistake.) 5. Give a complete proof by contradiction of the claim in item 4. (Recall. A number is rational iff it can be written as the quotient of two integers.)

Elements Of Modern Algebra
8th Edition
ISBN:9781285463230
Author:Gilbert, Linda, Jimmie
Publisher:Gilbert, Linda, Jimmie
Chapter2: The Integers
Section2.2: Mathematical Induction
Problem 50E: Show that if the statement 1+2+3+...+n=n(n+1)2+2 is assumed to be true for n=k, the same equation...
icon
Related questions
Question
Only number 5.
4. Explain what is wrong in the following "proof."
CLAIM. Let x be a real number. If x is irrational, then 2x is irrational.
"PROOF." Take r =
is irrational for any irrational number c.
V2. Then x is irrational, and so is 2x = 2/2. Therefore 2x
%3D
%3D
(Note. Find the mistakes in logical reasoning. "Lacks detail is not a mistake.)
5. Give a complete proof by contradiction of the claim in item 4. (Recall. A number
is rational iff it can be written as the quotient of two integers.)
Transcribed Image Text:4. Explain what is wrong in the following "proof." CLAIM. Let x be a real number. If x is irrational, then 2x is irrational. "PROOF." Take r = is irrational for any irrational number c. V2. Then x is irrational, and so is 2x = 2/2. Therefore 2x %3D %3D (Note. Find the mistakes in logical reasoning. "Lacks detail is not a mistake.) 5. Give a complete proof by contradiction of the claim in item 4. (Recall. A number is rational iff it can be written as the quotient of two integers.)
Expert Solution
steps

Step by step

Solved in 2 steps with 2 images

Blurred answer