JEE Main 2020 · MathsMultiple choiceSingle correctMediumMulti-step

JEE Main 2 September 2020, Shift 2, Maths Q61

Question 61 of 75 in this shift, Maths question 11 of 25.

Let

f:(-1,\infty)\to\mathbf{R}

be defined by

f(0)=1

and

f(x)=\frac{1}{x}\log_e(1+x)

x\neq 0

. Then the function

f

(1)decreases in $(-1,0)$ and increases in $(0,\infty)$ .
(2)increases in $(-1,0)$ and decreases in $(0,\infty)$ .
(3)increases in $(-1,\infty)$ .
(4)decreases in $(-1,\infty)$ .Official answer

Official answer

Option 4

NTA final key (Sep 2020).

Chapter: Application of Derivatives
Topic: Monotonicity
Idea tested: First Derivative Test

Same idea in other shifts

Asked 4× in all

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Question text from the official JEE Main paper published by NTA; answer from the final answer key. Chapter, topic and idea tags, difficulty and skill are Lumi’s. Lumi analyses 108 of the 174 JEE Main shifts held from 2017 to 2026.