JEE Main 2020 · MathsNumerical answerNumerical valueMediumMulti-step

JEE Main 6 September 2020, Shift 2, Maths Q73

Question 73 of 75 in this shift, Maths question 23 of 25.

Suppose that a function

f:\mathbf{R}\to\mathbf{R}

satisfies

f(x+y)=f(x)f(y)

for all

x,y\in\mathbf{R}

and

f(1)=3

. If

\sum_{i=1}^{n}f(i)=363

, then n is equal to ________.

Official answer

5.00

NTA final key (Sep 2020).

Chapter: Relations and Functions
Topic: AP and GP
Idea tested: GP Sum of n terms

Same idea in other shifts

Asked 10× 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.