Sat February 26, 2011 By:

from an external point P two tangents are drawn PA and PB and point P is joined to the centre of the circle O. prove that PA+PB=OP

Expert Reply
Sat April 02, 2011
Dear student
Following is the solution of your question
PA and PB are the tangents to the circle from external point P to the circle so they are equal in length.
i.e PA = PB
soif PA+PB =OP if 2PA=OP or PA/OP=1/2 =cos 60
So PA+PB=OP if the tangents at Pare inclined to each other at an angle of 120 degrees and not in general.
Hope it clarifies your doubt
Team topper
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