JEE Advanced2015MathematicsDefinite IntegrationActual
Let f ′ x = 192 x 3 2 + sin 4 ⁡ π x for all x ∈ R with f 1 2 = 0 . If m ≤ ∫ 1 2 1 f x d x ≤ M , then the possible values of m and M are
Options
- Am = 13 , M = 24
- Bm = 1 4 , M = 1 2
- Cm = - 11 , M = 0
- Dm = 1 , M = 12
Correct answer
D. m = 1 , M = 12
Step-by-step solution
Assuming f ( x ) to more increasing or less increasing 192 x 3 3 f ′ x 192 x 3 2 64 x 3 f ′ x 96 x 3 ∫ 64 x 3 d x ∫ f ′ x d x ∫ 96 x 3 d x 16 x 4 - 1 f x 24 x 4 - 3 2 ∫ 1 2 1 16 x 4 - 1 d x ∫ 1 2 1 f x d x ∫ 1 2 1 24 x 4 - 3 2 d x 26 10 ∫ 1 2 1 f x d x 78 20 Hence option m = 1 , M = 12 is correct.