Differential Equations with Boundary-Value Problems, Exercise 7.1, 11 to 18
Differential Equations with Boundary-Value Problems, Exercise 7.1, 1 to 6
WTW 256 Lecture Notes
All for this textbook (9)
Written for
Transformada de Funciones
All documents for this subject (1)
Seller
Follow
leomilenio1
Content preview
Dennis G. Zill - Differential Equations with
Boundary-Value Problems, Exercise 7.1. From 11 to 18
Leonardo J. Perez Gomez
14 de agosto de 2022
1. Let the figure 1
2.00
1.75
1.50
1.25
f(t)
1.00
0.75
0.50
0.25
0.00
0.00 0.25 0.50 0.75 1.00 1.25 1.50 1.75 2.00
t
Figura 1: Problem 7
0 0≤t<1
∴f (t) =
f1 (t) t≥1
If f1 (t) = t
0 0≤t<1
∴f (t) =
t t≥1
Z ∞ Z 1 Z ∞
∴ L {f (t)} = −st
e f (t)dt = −st
e (0)dt + e−st (t)dt
Z0 ∞ 0 1
= e−st (t)dt
1
1
, e−st (t)dt
R
1.
dv = e−st dt e−st t e−st
Z Z
u=t −st
−st ∴ e dt = − − − dt
du = dt v = − e s s s
e−st t 1 e−st t 1
Z −st
−st e
=− + e dt = − + −
s s s s s
−st −st
e t e t 1
=− − 2 = e−st − − 2
s s s s
b
t 1
∴ L {f (t)} = lı́m e − − 2 −st
b→∞ s s 1
−s 1 1
=e − − 2
s s
2. Let the figure 2
4.0
3.5
3.0
2.5
f(t)
2.0
1.5
1.0
0.5
0.0
0.0 0.5 1.0 1.5 2.0 2.5 3.0
t
Figura 2: Problem 8
0 0≤t<1
∴ f (t) =
f1 (t) t≥1
If f1 (t) = 2t − 2
0 0≤t<1
∴ f (t) =
2t − 2 t≥1
Z 1 Z ∞ Z ∞
∴ L {f (t)} = e −st
(0)dt + e−st
(2(t − 1))dt = e−st (2(t − 1))dt
0 1 1
2
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through EFT, credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying this summary from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller leomilenio1. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy this summary for R55,73. You're not tied to anything after your purchase.