Question

if a,b,c are three consecutive positive integers,show that,log(1+ac)=2logb

Answer 1

let us write a=b-1;c=b+1
log(1+(b-1)(b+1))=2logb
log(1+b^2-1)=2logb
logb^2=2logb
2logb=2logb
::hence proved