2 Dot Product 15 18. Use the Cauchy-Schwarz inequality to solve the following max/min problem: If the (long) diagonal of a rectangular box has length c, what is the greatest the sum of the length, width, and height of the box can be? For what shape box does the maximum occur? 19. Give an alternative proof of the Cauchy-Schwarz inequality, as follows. Let a = |x||, b = ||y||, and deduce from ||bx - ay l|20 that x y ab. Now how do you show that |x yl ab? When does equality hold? 20. (a) Letx and y be vectors with ||x || = lly|l. Prove that the vector x + y bisects the angle between x and y ||x || and b = ||y||. Prove that (b) More generally, if x and y are arbitrary nonzero vectors, let a the vector bx + ay bisects the angle between x and y. 21. Use vector methods to prove that the diagonals of a parallelogram bisect the vertex angles if and only if the parallelogram is a rhombus. 22. Given AABC with D on BC as shown in Figure 2.6. Prove that if AD bisects ZBAC, then BD|/CD| ||AB ||/|| A || . (Hint: Use Exercise 20b. Let x = AB and y = AC; give two expressions for AD in terms of x and y and use Exercise 1.1.10.)
2 Dot Product 15 18. Use the Cauchy-Schwarz inequality to solve the following max/min problem: If the (long) diagonal of a rectangular box has length c, what is the greatest the sum of the length, width, and height of the box can be? For what shape box does the maximum occur? 19. Give an alternative proof of the Cauchy-Schwarz inequality, as follows. Let a = |x||, b = ||y||, and deduce from ||bx - ay l|20 that x y ab. Now how do you show that |x yl ab? When does equality hold? 20. (a) Letx and y be vectors with ||x || = lly|l. Prove that the vector x + y bisects the angle between x and y ||x || and b = ||y||. Prove that (b) More generally, if x and y are arbitrary nonzero vectors, let a the vector bx + ay bisects the angle between x and y. 21. Use vector methods to prove that the diagonals of a parallelogram bisect the vertex angles if and only if the parallelogram is a rhombus. 22. Given AABC with D on BC as shown in Figure 2.6. Prove that if AD bisects ZBAC, then BD|/CD| ||AB ||/|| A || . (Hint: Use Exercise 20b. Let x = AB and y = AC; give two expressions for AD in terms of x and y and use Exercise 1.1.10.)
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
Topic Video
Question
Please help me solve problem 20. Thanks!

Transcribed Image Text:2 Dot Product
15
18. Use the Cauchy-Schwarz inequality to solve the following max/min problem: If the (long)
diagonal of a rectangular box has length c, what is the greatest the sum of the length, width, and
height of the box can be? For what shape box does the maximum occur?
19. Give an alternative proof of the Cauchy-Schwarz inequality, as follows. Let a = |x||, b = ||y||,
and deduce from ||bx - ay l|20 that x y ab. Now how do you show that |x yl ab? When
does equality hold?
20. (a) Letx and y be vectors with ||x || = lly|l. Prove that the vector x + y bisects the angle between
x and y
||x || and b = ||y||. Prove that
(b) More generally, if x and y are arbitrary nonzero vectors, let a
the vector bx + ay bisects the angle between x and y.
21. Use vector methods to prove that the diagonals of a parallelogram bisect the vertex angles if and
only if the parallelogram is a rhombus.
22. Given AABC with D on BC as shown in Figure 2.6. Prove that if AD bisects ZBAC, then
BD|/CD|
||AB ||/|| A || . (Hint: Use Exercise 20b. Let x = AB and y = AC; give two
expressions for AD in terms of x and y and use Exercise 1.1.10.)
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 5 steps with 4 images

Knowledge Booster
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.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,

