# Thread: seperation of variables help

1. ## seperation of variables help

use seperation of variables

y' = (t^2)*e^(y+2t)

i got the answer of y(t) = (t^3)/3-2t+c

but online it tells me its wrong =(
what am i doing wrong??

on another note i dont even know how to start this one:

2. Originally Posted by bsanghera
use seperation of variables

y' = (t^2)*e^(y+2t)

i got the answer of y(t) = (t^3)/3-2t+c

but online it tells me its wrong =(

what am i doing wrong??

on another note i dont even know how to start this one:

$e^{-y}dy = t^2 e^{2t}dt$

For the second

$
\frac{dy}{\cos^2 y} = \sec^2 y dy = \ln t \,dt
$
.

3. ok i got

tan y =1/t + C

from there i take the arctan(1/t + C)???
im really frustrated and am never to finish a problem off i hate this feeling =(
thank you for your patience with me

4. Originally Posted by bsanghera
ok i got

tan y =1/t + C

from there i take the arctan(1/t + C)???
im really frustrated and am never to finish a problem off i hate this feeling =(
thank you for your patience with me
You'll need to integrate the right hand side. You differentiated.