| x+6 | ||
∫ | ||
| x2+3 |
| x + 6 | xdx | dx | ||||
J = ∫ | dx = ∫ | + 6∫ | = J1 + 6J2 | |||
| x2 + 3 | x2 + 3 | x2 + 3 |
| xdx | ||
J1 = ∫ | ||
| x2 + 3 |
| 1 | dt | 1 | 1 | |||||
J1 = | ∫ | = | lnt = | ln(x2 + 3) | ||||
| 2 | t | 2 | 2 |
| dx | ||
J2 = ∫ | ||
| x2 + 3 |
| √3dt | √3 | dt | √3 | |||||
J2 = ∫ | = | ∫ | = | arctgt | ||||
| 3t2 + 3 | 3 | t2 + 1 | 3 |
| √3 | x | |||
J2 = | arctg | |||
| 3 | √3 |
| 1 | x | |||
J = J1 + 6J2 = | ln(x2 + 3) + 2√3arctg | + C | ||
| 2 | √3 |