# Differential Equation Transformation help

Watch
#1
Using the substitution , the differential equation

is transformed to

But I can't seem to find a general solution for the transformed equation.

Using an integrating factor of yields

But the required solution is
0
5 years ago
#2
(Original post by Zacken)
Using the substitution , the differential equation

is transformed to

But I can't seem to find a general solution for the transformed equation.

Using an integrating factor of yields

But the required solution is
I would suggest separating the variables instead of using an integrating factor.
1
#3
(Original post by SeanFM)
I would suggest separating the variables instead of using an integrating factor.
...I hate myself, that was so obvious. Thank you so much!

On the flip side though, why didn't the integrating factor method work?
0
5 years ago
#4
(Original post by Zacken)
...I hate myself, that was so obvious. Thank you so much!

On the flip side though, why didn't the integrating factor method work?
I'm not sure what would differentiate to give du/dx + e^u, but it's not e^x * e^u. You'd get a few more exponent terms when you use the product rule. But apart from that I don't really know.
0
#5
(Original post by SeanFM)
I'm not sure what would differentiate to give du/dx + e^u, but it's not e^x * e^u. You'd get a few more exponent terms when you use the product rule. But apart from that I don't really know.
I'd suspect it was function continuity but Q(x) = 0 is continuous and I'm not sure what assumption I'm violating for this differential equation to not be applicable to the integrating factor theorem.

Oh well, thanks anyway! +Rep.
0
X

new posts
Back
to top
Latest
My Feed

### Oops, nobody has postedin the last few hours.

Why not re-start the conversation?

see more

### See more of what you like onThe Student Room

You can personalise what you see on TSR. Tell us a little about yourself to get started.

### Poll

Join the discussion

#### Current uni students - are you thinking of dropping out of university?

Yes, I'm seriously considering dropping out (124)
14.55%
I'm not sure (36)
4.23%
No, I'm going to stick it out for now (260)
30.52%
I have already dropped out (22)
2.58%
I'm not a current university student (410)
48.12%