Verified Solution • 2025–26 Session moderate

QJEEM22Mab0ae: JEE Main 2022 Mathematics - Class 12 JEEM22Mab0ae Solution: If m and n respectively are the number of local maximum and…

If m and n respectively are the number of local maximum and local minimum points of the function f(x)=∫0x2t2−5t+42+etdtf(x) = \int\limits_0^{{x^2}} {{{{t^2} - 5t + 4} \over {2 + {e^t}}}dt} , then the ordered pair (m, n) is equal to

Multiple Choice Options

  • A (3, 2)
  • B (2, 3)
  • C (2, 2)
  • D (3, 4)

Step-by-Step Verified Solution

f(x)=∫0x2t2−5t+42+etdtf(x) = \int_0^{{x^2}} {{{{t^2} - 5t + 4} \over {2 + {e^t}}}dt}

f′(x)=2x(x4−5x2+42+ex2)=0f'(x) = 2x\left( {{{{x^4} - 5{x^2} + 4} \over {2 + {e^{{x^2}}}}}} \right) = 0

x=0x = 0 , or (x2−4)(x2−1)=0({x^2} - 4)({x^2} - 1) = 0

x=0,x = 0, x=±2, ±1x = \pm 2,\, \pm 1

Now, f′(x)=2x(x+1)(x−1)(x+2)(x−2)(ex2+2)f'(x) = {{2x(x + 1)(x - 1)(x + 2)(x - 2)} \over {\left( {{e^{{x^2}}} + 2} \right)}}

f'(x) changes sign from positive to negative at x = −- 1, 1 So, number of local maximum points = 2

f'(x) changes sign from negative to positive at x = −- 2, 0, 2 So, number of local minimum points = 3

∴\therefore m = 2, n = 3

Related Learning Resources & Exam Preparation