Question 745655
Think what happens as x gets more and more negative.  x+1 will become more and more negative.  {{{3^(x+1)}}} will be {{{1/(3^(-x))}}}, which approaches zero, because in this form, the exponent is positive and increases without bound.  Horizontal asymptote is y=0.


{{{graph(300,300,-30,5,-5,20,3^(x+1))}}}