Please check my work: verify that the equation is homogeneous

We can also express the equation as -(x/y) - 2(y/x) = dy/dx, which can be simplified to -(1/v) - 2v = v + xv'. By rearranging, we get x(dv/dx) + (1/v) + 3v = 0. We can then integrate both sides and solve for v to get the final solution. In summary, the equation is homogeneous and can be solved by substituting v = (y/x) and integrating both sides of the equation.
  • #1
darryw
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Homework Statement


verify the equation is homogeneous and solve.. thanks

(x^2 - 2y^2)dx + (xy)dy = 0

(x^2 - 2y^2) = -(xy)dy/dx

(x^2 - 2y^2)/-(xy) = dy/dx

-(x/y) - 2(y/x) = dy/dx



v = (y/x) .. y = vx and dy/dx = v + xv'




-(1/v) - 2v = v + xv'

x(dv/dx) + (1/v) + 3v = 0

3v + (1/v) = -x(dv/dx)

(3v + (1/v))/dv = -x/dx

(1/3v + v)dv = (1/x) dx

1/9v^3 + 1/2v^2 = ln|x| + c


Homework Equations





The Attempt at a Solution

 
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  • #2
The equation is homogeneous since it is a function of x and y with no constants. The solution is: 1/9v^3 + 1/2v^2 = ln|x| + c
 

1. What does it mean for an equation to be homogeneous?

A homogeneous equation is one in which all the terms have the same degree, meaning they have the same number of variables with the same exponent. For example, x^2 + 2xy + y^2 = 0 is a homogeneous equation because all the terms have a degree of 2.

2. How do you verify if an equation is homogeneous?

To verify that an equation is homogeneous, you simply need to check if all the terms have the same degree. If they do, then the equation is homogeneous. If not, then it is not homogeneous.

3. Can an equation be both homogeneous and non-homogeneous?

No, an equation can only be one or the other. If even one term has a different degree, then the equation is not homogeneous.

4. Why is it important to check if an equation is homogeneous?

Homogeneous equations have special properties that make them easier to solve. By verifying if an equation is homogeneous, you can determine the best method to solve it.

5. What are some examples of homogeneous equations?

Some examples of homogeneous equations are: x^2 + 2xy + y^2 = 0, 3x^3 + 6x^2y + 3xy^2 = 0, and 2x + 4y - 3z = 0. These equations all have terms with the same degree, making them homogeneous.

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