Answer
$\frac{1}{x-3}$
Work Step by Step
To simplify, divide both the numerator and denominator by their greatest common factor.
Use the the factorization to find the GCF.
$\frac{x+1}{x^2-2x-3}=\frac{(x+1)}{(x+1)(x-3)}=\frac{(x+1)\div(x+1)}{(x+1)(x-3)\div(x+1)}=\frac{1}{x-3}$