#e^[(x-1) - 1/2 (x-1)^2 + (x-1)^3 /3 -(x-1)^4 /4 + ....]# is equal to?

1 Answer
Jun 17, 2017

The answer is #=x#

Explanation:

Let #y=(x-1)#

The exponent is

#=y-y^2/2+y^3/3-y^4/4+................#

This series is

#ln(1+y)=y-y^2/2+y^3/3-y^4/4+................#

Replace #y# by #(x-1)#

#ln(1+y)=ln(1+x-1)=lnx#

Therefore,

#e^(ln(1+y))=e^lnx=x#