Expression 2: arc tangent left parenthesis, StartFraction, "n" Over "x" , EndFraction , right parenthesis minus pi 0 Superscript, 0 Superscript, negative "x" , Baseline , Baseline left parenthesis, 0 Superscript, 0 Superscript, negative "n" , Baseline , Baseline 2 minus 1 , right parenthesisarctannx−π00−x00−n2−1