What is the general solution of the differential equation? (3x^2+2y)dx+2xdy=0

Gauge Odom

Gauge Odom

Answered question

2022-09-08

What is the general solution of the differential equation?
( 3 x 2 + 2 y ) d x + 2 x d y = 0

Answer & Explanation

Caiden Li

Caiden Li

Beginner2022-09-09Added 17 answers

We can write the equation ( 3 x 2 + 2 y ) d x + 2 x d y = 0 as:

              2 x d y = - ( 3 x 2 + 2 y ) d x
2 x d y d x = - 3 x 2 - 2 y
d y d x + y x = - 3 2 x

This is a First Order DE of the form:

y ( x ) + P ( x ) y = Q ( x )

Which we know how to solve using an Integrating Factor given by:

I F = e P ( x )   d x

And so our Integrating Factor is:

I F = e 1 x   d x
        = e ln | x |
        = x

If we multiply by this Integrating Factor we will (by its very design) have the perfect differential of a product:

          d y d x + y x = - 3 2 x

x d y d x + y = - 3 2 x 2

    d d x ( x y ) = - 3 2 x 2

Which is now a separable DE, and we can separate the variables to get:

x y =   - 3 2 x 2   d x
x y = - 1 2 x 3 + A
y = - 1 2 x 2 + A x

Do you have a similar question?

Recalculate according to your conditions!

New Questions in Differential Equations

Ask your question.
Get an expert answer.

Let our experts help you. Answer in as fast as 15 minutes.

Didn't find what you were looking for?