Math 225 - Dierential Equations I
Assignment # 2
Brief Solutions
1. We wish to solve
yexy
1
y
dx + xexy +
x
y2
dy = 0
(1)
with initial condition y(1) = 1.
We rst rewrite the equation as
M (x, y)dx + N (x, y)dy = 0
where
1
M (x, y) = yexy ,
y
and
N (x, y)
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Math 225
Final Exam, Version Master
Mar 20th, 2013
INSTRUCTOR: Rebecca Tyson
COURSE: MATH 225
Irving K. Barber School
of Arts and Sciences
UBC Okanagan
Date: April 23rd Time: 9:00 AM Duration 3 hours.
This exam has 10 questions for a total of 55 points.
S
Math 225 - Dierential Equations I
Midterm # 1, Version A
February 6th, Duration: 80 minutes
Instructions: When answering questions, make sure it is clear how your solution is obtained
from the information given. There will be no marks for solutions withou
Math 225 - Dierential Equations I
Midterm # 1, Version B
February 6th, Duration: 80 minutes
Instructions: When answering questions, make sure it is clear how your solution is obtained
from the information given. There will be no marks for solutions withou
Math 225cfw_Mar 20th, 2013)
m
and 25 N/m spring
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l. A I kg massattached a springwith an 8 kgls da,rnpiag
constantis at equilibrium and givenan initial velocity of I m/s toward the right. Determine the eqrrationof motion for the mass.
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Math 225 (Mar 20th, 2013)
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Midterm ff2, Version1
I. A 1 kg ma^ss
attached to a spring with a 6 kgls daurping constant and 25 N/m spring
constant is initially displaced 1 m to the right of equilibrium and relea^sed.
Determine
the equation of motion for
Mar 20th. 2013
' Math 225 Final Exam, Version Master
INSTRUCTOR: REBECCA TYSON
COU RSE: MATH 225
IRVING K. BARBER SCHOOL
or Am AND SCIENCES
UBC OKANAGAN
OKANAGAN
me: 9:00 AM Duration 3 hours.
Date: April 23rd Ti
f 55 points.
This exam has 10 ques
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