Solve the following differential equation `dy/dx=e^(x+y)-1`.

Explanation

x+y=u

differentiate with respect to x

`1+y`=u'`

`y'=u'-1`

`e^x-1=u'-1`

`u'=e^x`

`inte^-x dx=intdx`

`-e^-x=x+c`

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