﻿ A circle C touches the x-axis and the circle x2 + (y – 1)2 = 1externally, then locus of the centre of the circle is given by : Kaysons Education

# A Circle C touches The x-axis And The Circle x2 + (y – 1)2 = 1externally, Then Locus Of The Centre Of The Circle Is Given By

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## Question

### Solution

Correct option is

All the circle having centre on the negative y-axis and passing through the origin touch the circle x2 + (y – 1)2 = 1 and the x-axis. Let A1 (0, 1) be the centre of the given circle and A2 (xy) be the centre of C. If r1r2be the radii of these circles then r1 + r2 = A1A2

Thus the locus of the centre is

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