JEE Main 2020 — Application Of Derivatives Question with Solution
From: JEE Main 2020 (Online) 8th January Morning Slot
Question
If c is a point at which Rolle's theorem holds
for the function,
f(x) = in the interval [3, 4], where a R, then ƒ''(c) is equal to
f(x) = in the interval [3, 4], where a R, then ƒ''(c) is equal to
Choose an option
Show full solutionCorrect option: A
Correct answer
A
Step-by-step explanation
For Rolle’s theorem to be applicable in [3, 4]
ƒ(3) = ƒ(4)
36 + 4 = 48 + 3
= 12
According to Rolle’s theorem, f'(c) = 0
where c (3, 4)
f'(x) =
f'(x) =
f'(c) =
From Rolle's theorem
= 0
c2 = 12
Now f''(c) =
=
=
ƒ(3) = ƒ(4)
36 + 4 = 48 + 3
= 12
According to Rolle’s theorem, f'(c) = 0
where c (3, 4)
f'(x) =
f'(x) =
f'(c) =
From Rolle's theorem
= 0
c2 = 12
Now f''(c) =
=
=
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