JEE Main 2021 · MathsNumerical answerNumerical valueMediumMulti-step

JEE Main 27 August 2021, Shift 2, Maths Q85

Question 85 of 90 in this shift, Maths question 25 of 30, Section B.

Two circles each of radius 5 units touch each other at the point

(1, 2)

. If the equation of their common tangent is

4x + 3y = 10

, and

C_1(\alpha, \beta)

and

C_2(\gamma, \delta)

C_1 \neq C_2

are their centres, then

|(\alpha + \beta)(\gamma + \delta)|

is equal to __________.

Official answer

NTA final key.

Chapter: Conic Sections
Topic: Circle Tangents
Idea tested: Common Tangent of Touching Circles

Same idea in other shifts

Asked 5× 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.