Question

Log осн.5 (x+1) +log осн5 (x-3)

Answer 1

ОДЗ x+1>0    x-3>0
          x>-1         x>3
x∈(3;+$infty$)

$log_5(x+1)+log_5(x-3)=log_5((x+1)(x-3))=log_5(x^2-2x-3)$

Answer 2

log5 ((x-+1)(x-3))=log(x^2-2x-3)