JEE Main202330 Jan 2023Evening ShiftMathematicsIndefinite IntegrationActual
If ∫ sec 2 x - 1 d x = α log e cos 2 x + β + cos 2 x 1 + cos 1 β x + constant, then β - α is equal to ______.
Correct answer
0
Step-by-step solution
Given, ∫ sec   2 x - 1 d x = α   log e cos   2 x + β + cos   2 x 1 + cos 1 β x + C Now solving L . H . S we get, ∫ sec   2 x - 1 d x = ∫ 1 - cos   2 x cos   2 x d x ⇒ ∫ sec   2 x - 1 d x = 2 ∫ sin   x 2 cos 2 x - 1 d x Now let cos   x = t   ⇒ - sin   x   d x = d t ⇒ ∫ sec   2 x - 1 d x = - 2 ∫ d t 2 t 2 - 1 ⇒ ∫ sec   2 x - 1 d x = - ln | 2 cos   x + c