JEE Main 2020 — Definite Integration Question with Solution
From: JEE Main 2020 (Online) 7th January Morning Slot
Question
If ƒ(a + b + 1 - x) = ƒ(x), for all x, where a and b are fixed positive real numbers, then
is equal to:
is equal to:
Choose an option
Show full solutionCorrect option: A
Correct answer
A
Step-by-step explanation
I = ...(1)
x a + b - x
I =
I = .....(2)
[As ƒ(x) = ƒ(a + b + 1 - x)
ƒ(x + 1) = ƒ(a + b - x)]
Adding (1) and (2) we get
2I =
I =
I =
I =
I =
Let x = t + 1
I =
=
x a + b - x
I =
I = .....(2)
[As ƒ(x) = ƒ(a + b + 1 - x)
ƒ(x + 1) = ƒ(a + b - x)]
Adding (1) and (2) we get
2I =
I =
I =
I =
I =
Let x = t + 1
I =
=
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This is a previous-year question from JEE Main 2020, covering the Definite Integration chapter of Mathematics. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.