$${\tan ^{ - 1}}\left( {x + {1 \over x}} \right) + C$$

$${\tan ^{ - 1}}\left( {x - {1 \over x}} \right) + C$$

$${\log _e}\left| {{{x + {1 \over x} - 1} \over {x + {1 \over x} + 1}}} \right| + C$$

$${\log _e}\left| {{{x - {1 \over x} - 1} \over {x - {1 \over x} + 1}}} \right| + C$$

| I | < 10^$$-$$9

| I | < 10^$$-$$7

| I | < 10^$$-$$5

| I | > 10^$$-$$7

2^x f'(x) + C

2^x log 2 + C

2^x f(x) + C

2^x + C