NTA Abhyas JEE Main2020MathematicsIndefinite IntegrationPractice
∫ ln x + 1 - ln x x x + 1 d x is equal to (where C is an arbitarary constant)
Options
- A- 1 2 ln x + 1 x 2 + C
- BC - ln x + 1 2 - ln x 2
- C- ln ln x + 1 x + C
- D- ln x + 1 x + C
Correct answer
A. - 1 2 ln x + 1 x 2 + C
Step-by-step solution
Put ln x + 1 - ln x = t ⇒ 1 x + 1 - 1 x = d t d x ⇒ x - x + 1 x x + 1 = d t d x ⇒ - d x x x + 1 = d t ⇒ d x x x + 1 = - d t so question becomes - ∫ t d t = - t 2 2 + C