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Friday, 9 October

JEE Main 2021 · MathsNumerical answerNumerical valueMediumMulti-step

JEE Main 3 August 2021, Shift 2, Maths Q86

Question 86 of 90 in this shift, Maths question 26 of 30, Section B.

The circles, x2+y2+2x+4y−4=0x^2 + y^2 + 2x + 4y - 4 = 0 and x2+y2−4x+4y+k=0x^2 + y^2 - 4x + 4y + k = 0 touch each other internally. If the point of contact of these circles is (a,b)(a, b), then 5(a2+b2)5(a^2 + b^2) is equal to ‾\underline{\hspace{2em}}.

Official answer

100

NTA final key.

Same topic in other shifts

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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 42 of the 174 JEE Main shifts held from 2017 to 2026.