JEE Main 2021 — Circle Question with Solution
From: JEE Main 2021 (Online) 27th August Evening Shift
Question
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 C1(, ) and C2(, ), C1 C2 are their centres, then |( + ) ( + )| is equal to ___________.
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Show full solutionCorrect answer: 40
Correct answer
40
Step-by-step explanation
Slope of line joining centres of circles =
Now using parametric form
(x, y) = (1 + 5cos, 2 + 5sin)
(, ) = (4, 6)
(x, y) = (, ) = (1 5cos, 2 5sin)
(, s) = (2, 2)
|( + ) ( + )| = | 10x 4 | = 40
Now using parametric form
(x, y) = (1 + 5cos, 2 + 5sin)
(, ) = (4, 6)
(x, y) = (, ) = (1 5cos, 2 5sin)
(, s) = (2, 2)
|( + ) ( + )| = | 10x 4 | = 40
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