(see instructions for Exercise 6 in Section 2.2): PROOF EVALUATION a) "THEOREM": For any sets A, B, and C, if A UB=AU C, then B = C. "Proof": We will prove this by contradiction. Suppose that A UB and A UC are not equal. Then there is some object x that is in one and not the other. We proceed by looking at two cases: First look at the case where xEA UB and not in A U C. Then x is not in A (be- cause, if it were, it would also be in A U C). So x must be in B (otherwise it wouldn't be in A U B). Also, x is not in C (because, if it were, it would also be in A U C). Therefore x is in B and not in C, which contradicts the condition B = C. The case where x EAU C and not in A U B is done by a parallel argument.
(see instructions for Exercise 6 in Section 2.2): PROOF EVALUATION a) "THEOREM": For any sets A, B, and C, if A UB=AU C, then B = C. "Proof": We will prove this by contradiction. Suppose that A UB and A UC are not equal. Then there is some object x that is in one and not the other. We proceed by looking at two cases: First look at the case where xEA UB and not in A U C. Then x is not in A (be- cause, if it were, it would also be in A U C). So x must be in B (otherwise it wouldn't be in A U B). Also, x is not in C (because, if it were, it would also be in A U C). Therefore x is in B and not in C, which contradicts the condition B = C. The case where x EAU C and not in A U B is done by a parallel argument.
Advanced Engineering Mathematics
10th Edition
ISBN:9780470458365
Author:Erwin Kreyszig
Publisher:Erwin Kreyszig
Chapter2: Second-order Linear Odes
Section: Chapter Questions
Problem 1RQ
Related questions
Question

Transcribed Image Text:(see instructions for Exercise 6 in Section 2.2):
PROOF EVALUATION
a) "THEOREM": For any sets A, B, and C, if A UB=AU C, then B = C.
"Proof": We will prove this by contradiction. Suppose that A UB and A UC are not
equal. Then there is some object x that is in one and not the other. We proceed by
looking at two cases:
First look at the case where x EA UB and not in A U C. Then x is not in A (be-
cause, if it were, it would also be in A U C). So x must be in B (otherwise it wouldn't
would also be in A U C).
be in A U B). Also, x is not in C (because, if it were,
Therefore x is in B and not in C, which contradicts the condition B
The case where x E AUC and not in A U B is done by a parallel argument.
= C.

Transcribed Image Text:PROOF EVALUATION (This type of exercise will appear occasionally): Each of the follow-
ing is a proposed "proof" of a "theorem". However the "theorem" may not be a true statement,
and even if it is, the "proof" may not really be a proof. You should read each "theorem" and
"proof" carefully and decide and state whether or not the "theorem" is true. Then:
G
If the "theorem" is false, find where the "proof" fails. (There has to be some error.)
. If the "theorem" is true, decide and state whether or not the "proof" is correct. If it is
not correct, find where the "proof" fails.
Expert Solution

This question has been solved!
Explore an expertly crafted, step-by-step solution for a thorough understanding of key concepts.
This is a popular solution!
Trending now
This is a popular solution!
Step by step
Solved in 3 steps

Recommended textbooks for you

Advanced Engineering Mathematics
Advanced Math
ISBN:
9780470458365
Author:
Erwin Kreyszig
Publisher:
Wiley, John & Sons, Incorporated

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…
Advanced Math
ISBN:
9781118141809
Author:
Nathan Klingbeil
Publisher:
WILEY

Advanced Engineering Mathematics
Advanced Math
ISBN:
9780470458365
Author:
Erwin Kreyszig
Publisher:
Wiley, John & Sons, Incorporated

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…
Advanced Math
ISBN:
9781118141809
Author:
Nathan Klingbeil
Publisher:
WILEY

Mathematics For Machine Technology
Advanced Math
ISBN:
9781337798310
Author:
Peterson, John.
Publisher:
Cengage Learning,

