If x=ey+ey+…∞,x>0, then dydx is equal to
x1+x
1x
1−xx
1+xx
given that, x=ey+ey+…⋅n
∴ x=ey+x
Taking log on both sides, we get
log x=(y+x)
On differentiating w.r.t. x, we get
1x=dydx+1⇒dydx=1−xx