# Dfq, Prove

1. Apr 3, 2005

### Naeem

Q. Prove that a separable differential equation must be exact.

Well, don't know no how to do this. There is no proof given in the text book.

All I know,

Mdx = Ndy ( Test for exactness )

Anybody here, any ideas

2. Apr 3, 2005

### Data

separable equation has the form

$$\frac{y^\prime}{f(y)} = g(x) \Longleftrightarrow g(x) - \frac{y^\prime}{f(y)} = 0$$

apply exactness test...