# Math Help - Differential equation formulation

1. ## Differential equation formulation

Hey all, just had a question about any approach to this problem I have:

Find a function f(y) with the property that: for each solution y(x) of dy/dx = f(y), the limiting value lim (x approaches infinity) y(x)=3 if y(0) > 0.

I'm not exactly too sure of where to start or go with this. Any help on this? Thanks plenty!

2. Originally Posted by lute
Hey all, just had a question about any approach to this problem I have:

Find a function f(y) with the property that: for each solution y(x) of dy/dx = f(y), the limiting value lim (x approaches infinity) y(x)=3 if y(0) > 0.

I'm not exactly too sure of where to start or go with this. Any help on this? Thanks plenty!
how about you start by finding a function $y(x)$ such that $\lim_{x \to \infty}y(x) = 3$ first. that shouldn't be too hard. then make a differential equation from it