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# ABC is a right angled triangle, right angled at C and pis the length of the perpendicular from C on AB. If a, band care the lengths of the sides BC, CA and AB respectively, then A. $1\over p^2$= $1\over b^2$-$1\over a^2$ B. $1\over p^2$= $1\over a^2$+$1\over b^2$ C. $1\over p^2$+ $1\over a^2$+$1\over b^2$ = 0D. $1\over p^2$= $1\over a^2$-$1\over b^2$

[ A ]    a
[ B ]    b
[ C ]    c
[ D ]    d
 Answer : Option B Explanation :