Archive for February, 2010

Emporium quiz

Friday, February 26th, 2010

I was wondering what are the quizzes that is going to be on the emporium quiz.

CANCELLED: 3:30 class and review session

Thursday, February 25th, 2010

Hi, folks:

I apologize for the very short notice, but I’m cancelling the 3:30 class and tonight’s review session due to a family emergency.

Unfortunately, I am not able to extend the deadline for this week’s Emporium quiz. That quiz covers sections 3.1 and 3.2, which we’ve already been over (it was the material on Homework 5). I’m cancelling Homework 6 this weekend to give people additional time to prepare for the quiz.

Again, I apologize for the short notice; thank you all for understanding.

Heath

hwk 5 #18

Sunday, February 21st, 2010

for the graphing matches, do i need to complete the square for the first problem? i turned it into the form x^2+2x then got x =0 and x=-2.
the general soultion became y= c1*e^0*t + c2*e^-2t so y=c1 +c2*e^-2t. is this the right track because when i tried solving for the C1 and C2 the answer didnt correlate to the graph. Thanks

Page 120, #10

Friday, February 19th, 2010

For my Wronksie, I got -ln(3)/t. Since this is undefined at t = 0, does that mean the two functions are not a fundamental set? Or since undefined is kind of nonzero, are they a fundamental set.

Notes for Day 11

Friday, February 19th, 2010

I don’t know if I am the only one having this problem, but when I try to print out the notes for Day 11 it does not take me to a pdf file. It takes me to a web page with an error message saying 404 Not found,

“Not Found

The requested URL /math2214/pdfs/2214-kj304.pdf was not found on this server.
Apache/2.2.12 (Ubuntu) Server at www.collegemath.org Port 80″

Could you make Notes for Day 11 available?

Thank you.

Example 4 (p.85) Exercise 3

Wednesday, February 17th, 2010

After integrating both sides you get v=v0/(1+(kt/m)*v0)
I was wondering how set up the variables for integration?
v’=-g-kv^2/m
I set g = to zero and could not get the right answer.
I was wondering where you would get the +1 without using g.

About Quiz 3

Tuesday, February 16th, 2010

Quiz 3 will take place during the last 15 minutes of class on Thursday. The format and length will be similar to Quiz 1, but the topics will come from sections 2.5, 2.6, 2.9 and 2.10, and can include:

  • Solve a nonlinear equation using separation of variables.
  • Solve a drag force problem when the drag force is proportional to velocity.
  • Use the formula v_{\infty} = -\frac{mg}{k} to find the terminal velocity of a falling point mass.
  • Set up a drag force problem when the drag force is proportional to the square of the velocity (be careful about the signs!)
  • Given a solution to an autonomous differential equation and an initial condition, find the solution that satisfies the initial condition.
  • Use the substitution \frac{dv}{dt} = \frac{dv}{dx}v to solve a differential equation
  • Use Euler’s Method to approximate the solution to a differential equation.

In class quiz 3

Tuesday, February 16th, 2010

I was wondering what topics are covered in quiz 3 for this thursday?
Thanks.

Mathmatica Problem for HW4

Monday, February 15th, 2010

I had just downloaded mathmatica today and I am unfamiliar with how to plug in the necessary file to solve the Euler’s method problem for pg. 99 #12. I was wondering if you could give me a quick procedure in explaining how to use mathmatica to solve the required problem.

Projectile motion

Monday, February 15th, 2010

Relating to page 80

In the book it says mv’=-mg-kv^2

It then seperates the variables and says it is v’/(1+kv^2/mg)= -g
What variables are being seperated? Why is g on both sides of this equation?