COMEDK2025MathematicsDefinite IntegrationActual
_ 6 ^ 3 1 1+ x d x=
Options
- A3
- B2
- C6
- D12
Correct answer
D. 12
Step-by-step solution
Let I = _ 6 ^ 3 1 1 + x dx . Using the property _ a ^ b f(x) dx = _ a ^ b f(a + b - x) dx , we have a + b = 6 + 3 = 2 . I = _ 6 ^ 3 1 1 + ( 2 - x) dx = _ 6 ^ 3 1 1 + x dx . I = _ 6 ^ 3 1 1 + 1 x dx = _ 6 ^ 3 x x + 1 dx . Adding the two expressions for I : 2I = _ 6 ^ 3 ( 1 1 + x + x 1 + x ) dx = _ 6 ^ 3 1 dx . 2I = [x]_ 6 ^ 3 = 3 - 6 = 6 . I = 12 . Answer: 12