MATH 215/255
Fall 2014
Assignment 8
due 11/19
3.4, 3.7, 3.5, 3.9
Solutions to selected exercises can be found in [Lebl], starting from page 303.
3.4.6: a) Find the general solution of x1 = 2x1 , x2 =
Math 215/255 Section 103 (Gustafson): Written Assignment
3 Solutions
1. Solve exercise 1.4.9 in the online text.
Solution: let
y (t) = the mass (in kg) of toxic substance in Lake 1 at time t (in hours
Math 215/255: Homework #4 Due Friday, March 17, 2017.
Turn in problems in correct order and STAPLE your work!
1. Exponential matrix.
Compute etA for the following matrices:
(a)
1
1
1
1
1
3
0
1
A1 =
(b
MATH 215/255
Fall 2015
Assignment 5
2.5.3, 2.6, 6.1
1
y + y + y = e2t sec(2t), < t < .
4
4
4
Hint: To use the method of variation of parameters, rewrite the DE so that the
coecient of y is 1 before so
MATH 215/255, Homework 3
1. Consider the ODE
y (t) = y t,
y(0) = 2.
(1)
(a) Find the exact solution to this problem, and show that y(1) 4.71xx. What are the next two
digits xx?
(b) Use Eulers method t
HOMEWORK 1 SOLUTIONS: MATH 215
Problem 1: In each case, solve for y (t):
a. y + 2y = 0 with y (0) = 1.
b. y + 2y = 3et with y (0) = 2.
1
c. y 2y = te2t with y ( 4 ) = 0.
d. ty 2y = t3 sin t with y ( )
HOMEWORK 1: MATH 215
Due in class on Monday, Jan 20th
Show all relevant work for credit. You will be marked for your work and your answer as appropriate.
Working with others is encouraged but you must
MATH 215/255
Fall 2015
Assignment 2
Due date: October 02, 2015
1.4, 1.6, Brauns Book 1.9
1. Consider a pond that initially contains 10 million gal of fresh water. Water containing an undesirable chemi
HOMEWORK 2: Math 215 January 2014
1. Find the solution y(t) to
y =
3 2
1 2
y,
with y(0) =
3
3
.
Also, describe the behavior of the solution for large t.
2. Solve the following system of dierential equ
MATH 215/255
Fall 2015
Assignment 4
Due date: October 23, 2015
1. A small object of mass 1 kg is attached to a spring with spring constant 2 N/m. This
spring-mass system is immersed in a viscous mediu
HOMEWORK 1: MATH 215/255
Due in class on Friday, Jan 22nd
Show all relevant work for credit. You will be marked for your work and your answer as appropriate.
Talking to other students about the proble
Notes on Diffy Qs
Differential Equations for Engineers
by Ji Lebl
r
October 20, 2014
2
A
Typeset in LTEX.
Copyright c 20082014 Ji Lebl
r
This work is licensed under the Creative Commons Attribution-No
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MATH 215: MIDTERM 1: February 6th 2015
Closed Book and Notes. 50 minutes. Total 50 points
PROBLEwW'i; (28 Points) Solve the ioilowing initial value problems for y(t) and then
determine the interval
MATH 215: MIDTERM 2: MARCH 20th 2014. (R. Froese, M. Ward)
Closed Book and Notes. 50 minutes. Total 50 points
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COURSE OUTLINE FOR MATH 215: DIFFERENTIAL EQUATIONS
Text: We will use the free online text in .pdf form Diy Qs: Dierential Equations
for Engineers, by Jiri Lebl. Please download the book from:
http:/w
PROBLEM 3: (20 Points)
By using Laplace transforms, ﬁnd the solution to the initial value problem
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INTRODUCTION
TO REAL ANALYSIS
William F. Trench
Andrew G. Cowles Distinguished Professor Emeritus
Department of Mathematics
Trinity University
San Antonio, Texas, USA
[email protected]
This book has
Introduction to
Economic Analysis
Version 2.1
R. Preston McAfee;Tracy Lewis;Donald J. Dale
Introduction to Economic Analysis
1-1
About the Authors
ABOUT R. PRESTON MCAFEE
R. Preston McAfee received hi
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HOMEWORK 3: Math 215/255 October 2017
Part2
8. Analytically, find the solution y(t) to
2 7
0
y =
y,
1 2
with y(0) =
1
1
.
Use Matlab to plot the direction field for this system. You can use the upload
HOMEWORK 4: MATH 215/255 Fall 2017
Due in class Friday, November 10. Answer problems in the correct order. Staple your work.
1. Compute etA for the following matrices:
(a)
1
1
1
1
1
3
0
1
A1 =
(b)
A2
HOMEWORK 3: Math 215/255 October 2017
Part1 - Solutions
1. Find the solution y(t) to
0
y =
3 2
1 2
y,
with y(0) =
3
3
.
Also, describe the behavior of the solution for large t.
Solution: Problem 1:
Th
Math 215/255
Midterm 2, March 22, 2017
Name:
SID:
Instructor:
Section:
Instructions
The total time allowed is 50 minutes.
The total score is 40 points.
Use the reverse side of each page if you need