Solving ODE via Separation Method: Need Assistance

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Mugged
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Can anyone help me solve this ODE:
..in other words, find a general solution?

dy/dx = e^(x+y)

I use a separation method, but i can't take the natural log of -e^(-y).
So, help?
 
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Perhaps you can move the minus in front of e-y to the other side of your equation before you apply log.
 
Looks to me like you have forgotten the constant of integration. You should get something like [itex]y= -ln(C- e^x)[/itex] which exists only for [itex]C> e^x[/itex] or [itex]x< ln(C)[/itex]
 
Mugged said:
Can anyone help me solve this ODE:
..in other words, find a general solution?

dy/dx = e^(x+y)

I use a separation method, but i can't take the natural log of -e^(-y).
So, help?

e^(x+y) = e^x * e*y
e^(-y) dy = e^x dx
integrate both sides