c2ln(1ab)c^{2} \ln \left(\frac{1}{a b}\right)c2ln(ab1)
c2ln(ba)c^{2} \ln \left(\frac{b}{a}\right)c2ln(ab)
c2ln(ab)c^{2} \ln (a b)c2ln(ab)
c2ln(ab)c^{2} \ln \left(\frac{a}{b}\right)c2ln(ba)