Math 412 Week #11 Practice Quiz - Prof. Scott Annin, Quizzes of Mathematics

The solutions to problem 1, 2, and 3 from the math 412 week #11 practice quiz. Problem 1 involves evaluating integrals along straight lines and semicircular arcs. Problem 2 deals with proving a property of complex-valued functions. Problem 3 requires showing that the integral of a function over the boundary of a triangle is less than or equal to 60.

Typology: Quizzes

Pre 2010

Uploaded on 08/18/2009

koofers-user-2p9-1
koofers-user-2p9-1 ๐Ÿ‡บ๐Ÿ‡ธ

9 documents

1 / 2

Toggle sidebar

This page cannot be seen from the preview

Don't miss anything!

bg1
April 13-17, 2009 Week #11 Practice Quiz Name:
Math 412
Problem 1.
(a): (6 points) Evaluate
ZC1
z3dz,
where C1is a straight line from the origin to 2 + i.
(b): (4 points) Evaluate
ZC2
z3dz,
where C2is the path from 2 + ito the origin consisting of straight segments from 2 + ito 3 โˆ’2i,
from 3 โˆ’2ito โˆ’5i, from โˆ’5ito โˆ’2, and the lower semicircular arc of C1(โˆ’1) from โˆ’2 to the origin.
pf2

Partial preview of the text

Download Math 412 Week #11 Practice Quiz - Prof. Scott Annin and more Quizzes Mathematics in PDF only on Docsity!

April 13-17, 2009 Week #11 Practice Quiz Name:

Math 412

Problem 1.

(a): (6 points) Evaluate โˆซ

C 1

z

3 dz,

where C 1 is a straight line from the origin to 2 + i.

(b): (4 points) Evaluate โˆซ

C 2

z

3 dz,

where C 2 is the path from 2 + i to the origin consisting of straight segments from 2 + i to 3 โˆ’ 2 i,

from 3 โˆ’ 2 i to โˆ’ 5 i, from โˆ’ 5 i to โˆ’2, and the lower semicircular arc of C 1 (โˆ’1) from โˆ’2 to the origin.

Problem 2. (4 points) Let f (t) = u(t) + iv(t) be a complex-valued function of t โˆˆ R. Let

c + id โˆˆ C. Prove formally that

b

a

(c + id)f (t)dt = (c + id)

b

a

f (t)dt.

Problem 3. (6 points) Let C denote the boundary of the triangle with vertices at z = 0, z = โˆ’4,

and z = 3i, with positive orientation. Show that

C

(e

z โˆ’ z ) dz

[Hint: Write e

z โˆ’ z = e

z

  • (โˆ’z) and use the triangle inequality.]