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JEE Main Mathematics Limits 2026 JEE Main 2026 (21 January Shift 1)

JEE Main Mathematics Question (2026) — Solution

Question

Let f: R (0, ) be a twice differentiable function such that f(3)=18, f^ (3)=0 and f^ (3)=4. Then _ x 1 ( _ e ( f(2+x) f(3) )^ 18 (x-1)^ 2 ) is equal to :

Options

  1. A. 1
  2. B. 18
  3. C. 2
  4. D. 9

Answer

C. 2

Step-by-step solution

Let T = _ x 1 ( f(x+2) f(3) )^ 18 (x-1)^2 ; 1^ form T = e^ _ x 1 18 (x-1)^2 ( f(x+2) - f(3) f(3) ) T = e^ _ x 1 18 (x-1)^2 ( f(x+2) - f(3) 18 ) T = e^ _ x 1 ( f(x+2) - f(3) (x-1)^2 ) 0 0 form, apply L'pital T = e^ _ x 1 f'(x+2) 2(x-1) ; 0 0 form, apply L'pital T = e^ _ x 1 f''(x+2) 2 = e^ 4 2 = e^2 _e(T) = 2

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