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Two circles of radii `r_(1)` and `r_(2), r_(1) gt r_(2) ge2` touch each other externally. If `theta` be the angle between the direct common tangents, then,

A

`theta=sin^(-1)((r_1+r_2)/(r_1-r_2))`

B

`theta=2sin^(-1)((r_1-r_2)/(r_1+r_2))`

C

`theta=2cos^(-1)((2sqrt(r_1r_2))/(r_1+r_2))`

D

none of these

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The correct Answer is:
B, C
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