Expression 1: left parenthesis, StartFraction, 1 Over 1 minus "e" Superscript, left parenthesis, negative StartNestedFraction, 1 NestedOver "e" Superscript, "x" , Baseline , EndNestedFraction , right parenthesis , Baseline , EndFraction , right parenthesis negative "e" Superscript, "x" , Baseline minus 1 half11−e−1ex−ex−12