Is the Differential Equation (2y - e^x)y' = ye^x Exact or Solvable?

Click For Summary
SUMMARY

The differential equation (2y - e^x)y' = ye^x is not exact, as determined by the calculations of M and N where M = (2y - e^x) and N = (ye^x). The derivatives dM/dx and dN/dy yield -e^x and e^x respectively, confirming the equation's non-exactness. To solve this initial value problem with y(0) = 1, one must rewrite the equation in the form Mdy + Ndx = 0, leading to (2y - e^x)dy - ye^xdx = 0.

PREREQUISITES
  • Understanding of first-order differential equations
  • Familiarity with exact equations and their properties
  • Knowledge of initial value problems in calculus
  • Basic skills in manipulating differential forms
NEXT STEPS
  • Study the method for solving non-exact differential equations
  • Learn about integrating factors for first-order equations
  • Explore the theory behind exact differentials and their applications
  • Practice solving initial value problems with varying conditions
USEFUL FOR

Students and educators in mathematics, particularly those focusing on differential equations, as well as anyone seeking to improve their problem-solving skills in calculus.

Pengwuino
Gold Member
Messages
5,112
Reaction score
20
I hate this stuff! :cry: :cry:

The next problem I must face upon my path of enlightenment is the following:

Solve the initial value problem:

[tex](2y - e^x )y' = ye^x ,y(0) = 1[/tex]

I thought that it looked exact but I ended up with…

[tex]\begin{array}{l}<br /> M = (2y - e^x )dy,N = (ye^x )dx \\ <br /> \frac{{dM}}{{dx}} = - e^x ,\frac{{dN}}{{dy}} = e^x \\ <br /> \end{array}[/tex]

So it's not exact… how should I go about solving this? I really suck at these differentials by the way!
 
Physics news on Phys.org
You have my permission to kick yourself in the behind!

(2y- ex)y'= yex is the same as

(2y- ex)dy= yexdx but in order to check if it is an exact differential, you must write it as Mdy+ Ndx= 0.
That is: (2y-ex)dy- yexdx= 0
 

Similar threads

  • · Replies 3 ·
Replies
3
Views
1K
  • · Replies 18 ·
Replies
18
Views
3K
  • · Replies 2 ·
Replies
2
Views
1K
  • · Replies 8 ·
Replies
8
Views
2K
Replies
3
Views
2K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 5 ·
Replies
5
Views
2K
  • · Replies 8 ·
Replies
8
Views
2K
  • · Replies 5 ·
Replies
5
Views
2K
  • · Replies 1 ·
Replies
1
Views
2K