The differential equation corresponding to primitive y=edx is
or
The elimination of the arbitrary constant m from the equation y=emx gives the differential equation
[MP PET 1995, 2000; Pb. CET 2000]
dydx=(yx)log y
y=emx⇒log y mx⇒m=log yxy=emx⇒dydx=memx=log yxy=(yx) log y.