Question

ABC is a right- angled at C .If p is the length of the perpendicular from C to AB and a,b and c have the usaual meaning .then prove that : (1) cp = ab. (2) 1/p2 = 1/a2 + 1/b2

Answer 1

1)area of ∆ABC=p*c
Also area of ∆ABC=a*b
Therefore p*c=a*b