AP EAMCET201825 Apr 2018Morning ShiftMathematicsDefinite IntegrationActual
∫ 0 π x tan x sec x + tan x d x =
Options
- Aπ - 2 2
- Bπ + 2 2
- Cπ ( π + 2 ) 2
- Dπ ( π - 2 ) 2
Correct answer
D. π ( π - 2 ) 2
Step-by-step solution
Let I = ∫ 0 π x tan x sec x + tan x d x = ∫ 0 π π - x tan π - x sec π - x + tan π - x d x = ∫ 0 π π - x - tan x - sec x - tan x d x = ∫ 0 π π - x tan x sec x + tan x d x = ∫ 0 π π tan x sec x + tan x d x - ∫ 0 π x tan x sec x + tan x d x = ∫ 0 π π tan x sec x + tan x d x - I ⇒ 2 I = π ∫ 0 π tan x sec x + tan x d x ⇒ 2 I = π ∫ 0 π sin x cos x 1 cos x + sin x