JEE Main 2021 · MathsMultiple choiceSingle correctEasyApplication

JEE Main 26 February 2021, Shift 2, Maths Q68

Question 68 of 90 in this shift, Maths question 8 of 30, Section A.

Let

f(x)

be a differentiable function at

x=a

with

f'(a)=2

and

f(a)=4

. Then

\lim_{x \to a} \frac{xf(a)-af(x)}{x-a}

equals :

(1) $2a-4$
(2) $4-2a$ Official answer
(3) $2a+4$
(4) $a+4$

Official answer

Option 2

NTA final key.

Chapter: Continuity and Differentiability
Topic: Continuity and Differentiability
Idea tested: LHD and RHD Calculation

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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.