The two circles touch each other if
As we learnt in
Common tangents of two circles -
When two circles touch each other externally, there are three common tangents, two of them are direct.
- wherein
and
Common tangents of two circles -
When two circles touch each other internally, there is only one common tangent.
- wherein
They can touch internally or externally
Internally,
We get,
Externally,
So,
Option 1)
This option is incorrect
Option 2)
This option is incorrect
Option 3)
This option is incorrect
Option 4)
This option is correct
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