JEE Main201912 Apr 2019Morning ShiftMathematicsIndefinite IntegrationActual
The integral ∫ 2 x 3 - 1 x 4 + x d x , is equal to
Options
- A1 2 l o g e ( x 3 + 1 ) 2 | x 3 | + C
- Bl o g e | x 3 + 1 | x 2 + C
- Cl o g e x 3 + 1 x + C
- D1 2 l o g e | x 3 + 1 | x 2 + C
Correct answer
C. l o g e x 3 + 1 x + C
Step-by-step solution
I = ∫ 2 x 3 - 1 x 4 + x d x ⇒ I = ∫ 2 x - 1 x 2 x 2 + 1 x d x Put, x 2 + 1 x = t ⇒ 2 x - 1 x 2 d x = d t ∴ I = ∫ d t t = l o g e t + C = l o g e x 2 + 1 x + C = l o g e x 3 + 1 x + C