Got Homework?
Connect with other students for help. It's a free community.
Here's the question you clicked on:
 0 viewing
Waynex
Group Title
I have a question about the unit step function in a differential equation. Here is a link to the "quiz" this comes from: http://ocw.mit.edu/courses/mathematics/1803scdifferentialequationsfall2011/unitiiifourierseriesandlaplacetransform/unitstepandunitimpulseresponse/MIT18_03SCF11_s25_3quizq.pdf
I will post the result I obtained in a followup post where I can actually use LaTeX.
 11 months ago
 11 months ago
Waynex Group Title
I have a question about the unit step function in a differential equation. Here is a link to the "quiz" this comes from: http://ocw.mit.edu/courses/mathematics/1803scdifferentialequationsfall2011/unitiiifourierseriesandlaplacetransform/unitstepandunitimpulseresponse/MIT18_03SCF11_s25_3quizq.pdf I will post the result I obtained in a followup post where I can actually use LaTeX.
 11 months ago
 11 months ago

This Question is Closed

Waynex Group TitleBest ResponseYou've already chosen the best response.0
For v(t), I obtained: \[ce^{kt}, t < 0; ce^{kt}+\frac{1}{k}, t > 0.\] With the given initial condition, c = 0, and v(t) becomes: \[0, t < 0; \frac{1}{k}, t > 0.\] Then the derivative of that is delta(t), is it not? Then delta(0+) = 0. However, the soln given is delta(0+) = 1. http://ocw.mit.edu/courses/mathematics/1803scdifferentialequationsfall2011/unitiiifourierseriesandlaplacetransform/unitstepandunitimpulseresponse/MIT18_03SCF11_s25_3quiza.pdf
 11 months ago

Waynex Group TitleBest ResponseYou've already chosen the best response.0
It looks like where I went wrong was in assuming c to be the same for both parts of the piecewise solution. What I should have had for v(t) is:\[c_1e^{kt}, t < 0; c_2e^{kt}+\frac{1}{k}, t > 0.\]such that \[c_1 = 0; c_2 = \frac{1}{k}\]
 11 months ago
See more questions >>>
Your question is ready. Sign up for free to start getting answers.
spraguer
(Moderator)
5
→ View Detailed Profile
is replying to Can someone tell me what button the professor is hitting...
23
 Teamwork 19 Teammate
 Problem Solving 19 Hero
 Engagement 19 Mad Hatter
 You have blocked this person.
 ✔ You're a fan Checking fan status...
Thanks for being so helpful in mathematics. If you are getting quality help, make sure you spread the word about OpenStudy.