JEE Main20199 Apr 2019Morning ShiftMathematicsIndefinite IntegrationActual
∫ s e c 2 x · cot 4 3 x d x is equal to
Options
- A3 t a n - 1 3 x + C
- B- 3 4 t a n - 4 3 x + C
- C- 3 t a n - 1 3 x + C
- D- 3 c o t - 1 3 x + C
Correct answer
C. - 3 t a n - 1 3 x + C
Step-by-step solution
Given integral can be written as I = ∫ sec 2 x tan x 4 3   d x Let tan x = t ⇒ sec 2 x d x = d t ⇒ I = ∫ t - 4 3   d t Using ∫ x n d x = x n + 1 n + 1 + C , we get I = t - 1 3 - 1 3 +   C ⇒ I = - 3 t 1 3 +   C ⇒ I = - 3 tan - 1 3 x + C .