Q23 of 85 Page 233

Prove that the product of the lengths of the perpendiculars drawn from the points and to the line

The equation of the given line is



⇒ bxcosƟ + aysinƟ – ab = 0 ……………….(1)


Length of the perpendicular from point to line (1) is



--------------- (2)


Length of the perpendicular from point to line (2) is



--------------- (3)


On multiplying equations (2) and (3), we get,













Hence Proved.


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