12. We consider whether the inequality ||u||L² (n) ≤ c||L(u)||L² (2) can hold for open sets that are unbounded. (a) Assume d≥2. Show that for each constant coefficient partial differential operator L, there are unbounded connected open sets for which the above holds for all u € Co (N). (b) Show that ||u|| 1² (Rª) ≤ C||L(u)|| L² (Rª) for all u € C° (Rª) if and only if |P(§)| ≥ c> 0 all , where P is the characteristic polynomial of L.

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
Question
12. We consider whether the inequality
||u|| L² (2) ≤c||L(u) || L² (12)
can hold for open sets that are unbounded.
(a) Assume d≥2. Show that for each constant coefficient partial differential
operator L, there are unbounded connected open sets for which the above
holds for all u € Co (N).
(b) Show that ||u|| ₁² (Rd) ≤ C||L(u)||L2 (Rd) for all u € Co (R) if and only if
|P(§)| ≥ c > 0 all , where P is the characteristic polynomial of L.
[Hint: For (a) consider first L = (0/0x₁)" and a strip {x: −1 < x₁ < 1}.]
Transcribed Image Text:12. We consider whether the inequality ||u|| L² (2) ≤c||L(u) || L² (12) can hold for open sets that are unbounded. (a) Assume d≥2. Show that for each constant coefficient partial differential operator L, there are unbounded connected open sets for which the above holds for all u € Co (N). (b) Show that ||u|| ₁² (Rd) ≤ C||L(u)||L2 (Rd) for all u € Co (R) if and only if |P(§)| ≥ c > 0 all , where P is the characteristic polynomial of L. [Hint: For (a) consider first L = (0/0x₁)" and a strip {x: −1 < x₁ < 1}.]
Expert Solution
steps

Step by step

Solved in 4 steps

Blurred answer
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,