Same chapter3 marksDifficulty: Medium
Why can a tangent not be constructed from a point inside a circle?
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3 marksDifficulty: Medium
In constructing tangents from an external point P to a circle with centre O, why is a circle drawn on OP as diameter?
Original Khojo Papers practice question — not from a past board paper.
Answer
Any point on a circle with OP as diameter sees OP at a right angle, by the angle in a semicircle theorem. Where that circle cuts the given circle, the radius meets the line from P at 90°, which is exactly the condition for that line to be a tangent.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
The construction gives the two points of contact directly.
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