To prove:
a−1b−1+b−1c−1+c−1a−1a+b+c=abc
Solving L.H.S. of the above equation, we get :
⇒a−1b−1+b−1c−1+c−1a−1a+b+c=ab1+bc1+ca1a+b+c=abcc+a+ba+b+c=a+b+cabc(a+b+c)=abc.
Since, L.H.S. = R.H.S. = abc.
Hence, proved that a−1b−1+b−1c−1+c−1a−1a+b+c=abc.