Differential equation help! (1 Viewer)

[kfnmpah]

hey everyone, i need some help with this DE:

i) differentiate y=1/(Be^(-x)+1)
y' = Be^x/((e^x+B)^2)

then,
ii) is this a solution to y'=y(1-y)

any help would be much appreciated. I've plugged the values in but it doesn't seem to want to work for me.

thanks,
Nicola.

 

[Drongoski]

hey everyone, i need some help with this DE:

i) differentiate y=1/(Be^(-x)+1)
y' = Be^x/((e^x+B)^2)

then,
ii) is this a solution to y'=y(1-y)

any help would be much appreciated. I've plugged the values in but it doesn't seem to want to work for me.

thanks,
Nicola.

When you substitute: into y(1-y) you get



i.e. is a solution of the differential equation.


Edit

Amended

 

[kfnmpah]

But y' has e^x not e^-x? I mightj ust be missing something silly... but how???

 

[Drongoski]

But y' has e^x not e^-x? I mightj ust be missing something silly... but how???

Misread expression. Amended.