Determining vector in a direction field

In summary: The differential equation is y'= 1+ 2ty. That means that the slope at any point is just 1+ 2ty, the vector must have slope 1+ 2ty. That means that the two components must be equal, if the vector is <x, y>, then y/x= 1+ 2ty.In summary, the vector in the direction field at point (2,0) is <1,1> and the vector at point (3,-2) is <1,-11>.
  • #1
kpou
25
0

Homework Statement



Determine the vector in the direction field( in the form of < 1, ? >) correspond-
ing to the given point.
y' = 1 + 2ty at (2, 0), at (3, -2).

Homework Equations


The Attempt at a Solution



y'-2ty=1
p(t)=-2t ; u(t)=e^(-t^2)
e^(-t^2)-2te^(-t^2)=e^(-t^2)
e^(-t^2)=integral(e^(-t^2)dt)+c

I am confused where to go from here. I think I am supposed to set up the integral definitely. When i do from 0->0 I get c=2.
From here I am not sure where to go. Do I set up the integral from 0->1 (since I am trying to find a vector with t =1)? When I do this it comes out to <1, 2.63> What made me doubt this was how I am supposed to set up the problem at point (3,-2).

Do I plug in t=0 and for the integral do 0->1 ?

And plug in t=3 and do 3->4 integral ?

This does not really seem right though -.-

My weakness may lie in the fact that I have no notes on how to find a vector <1, ?>.
 
Last edited:
Physics news on Phys.org
  • #2
you are asked to find the direction field. That means that you do NOT want to solve the equation and do NOT want to integrate. All the information you need is in the differential equation.

At (2, 0) (which I am going to interpret as t= 2, y= 0) dy/dt= 1+ 2(2)(0)= 1 so your vector must have slope 1: the two components must be equal, if the vector is <x, y>, then y/x= 1.

At (3, -2), dy/dt= 1+ 2(3)(-2)= -11. The slope must be -11: if the vector is <x, y>, then y/x= -11.

In fact, this whole problem is pretty close to being trivial!
 

What is a direction field?

A direction field is a visual representation of the direction and magnitude of a vector at each point in a given region.

Why is determining vector in a direction field important in science?

Determining vector in a direction field allows scientists to understand the behavior and movement of a system or phenomenon. This information can be used to make predictions and further investigate the underlying principles at work.

How do you determine the vector in a direction field?

To determine the vector in a direction field, you need to first identify the direction and magnitude of the vector at a given point. This can be done by analyzing the slope of the direction field and using mathematical equations to calculate the magnitude.

What tools are commonly used to determine vector in a direction field?

Some common tools used to determine vector in a direction field include graphing calculators, computer software programs, and hand-drawn sketches. These tools can help visualize the direction field and make accurate calculations.

What are some real-world applications of determining vector in a direction field?

Determining vector in a direction field has many practical applications in various scientific fields, such as physics, engineering, and meteorology. It can be used to analyze the movement of fluids, study the behavior of electric and magnetic fields, and predict the path of weather systems.

Similar threads

  • Calculus and Beyond Homework Help
Replies
2
Views
132
  • Calculus and Beyond Homework Help
Replies
3
Views
308
  • Calculus and Beyond Homework Help
Replies
24
Views
782
  • Calculus and Beyond Homework Help
Replies
12
Views
977
  • Calculus and Beyond Homework Help
Replies
3
Views
557
  • Calculus and Beyond Homework Help
Replies
5
Views
1K
  • Calculus and Beyond Homework Help
Replies
2
Views
363
  • Calculus and Beyond Homework Help
Replies
1
Views
692
  • Calculus and Beyond Homework Help
Replies
3
Views
744
  • Calculus and Beyond Homework Help
Replies
8
Views
1K
Back
Top