﻿ If a > 2b > 0 then the positive value of m for which  is a common tangent to x2 + y2 = b2 and (x – a)2+ y2 = b2 is      : Kaysons Education

# If a > 2b > 0 Then The Positive Value Of m for Which  is A Common Tangent To x2 + y2 = b2 and (x – a)2+ y2 = b2 is

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## Question

### Solution

Correct option is

is a tangent to the circle x2 + y2 = b2 for all values of m. If it also touches the circle (x – a)2 + y2 = b2, then the length of the perpendicular from its centre (a, 0) on this line is equal to the radius b of the circle, which gives

Taking negative value on R.H.S. we get m = 0, so we neglect it.

Taking the positive value on R.H.S. we get

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