Mathematics · 2019
JEE Main · 9 January 2019, Shift 1 · Q80
Three circles of radii a, b, c ( a < b < c ) touch each other externally. If they have x -axis as a common tangent, then:
Three circles of radii $\displaystyle \mathrm{a}, \mathrm{b}, \mathrm{c}(\mathrm{a}<\mathrm{b}<\mathrm{c})$ touch each other externally. If they have $\displaystyle x$-axis as a common tangent, then :
Official answer
(3)
$\displaystyle \frac{1}{\sqrt{a}}=\frac{1}{\sqrt{b}}+\frac{1}{\sqrt{c}}$
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JEE Main 2019 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.