Question Number 109264 by mathdave last updated on 22/Aug/20
Answered by Her_Majesty last updated on 22/Aug/20
$${x}−\mathrm{1}={a}\wedge{x}+\mathrm{1}={b} \\ $$$${ln}^{\mathrm{2}} {ab}−{ln}^{\mathrm{2}} \frac{{a}}{{b}}=\left({lna}+{lnb}\right)^{\mathrm{2}} +\left({lna}−{lnb}\right)^{\mathrm{2}} = \\ $$$$={ln}^{\mathrm{2}} {a}+\mathrm{2}{lnalnb}+{ln}^{\mathrm{2}} {b}−{ln}^{\mathrm{2}} {a}+\mathrm{2}{lnalnb}−{ln}^{\mathrm{2}} {b}= \\ $$$$=\mathrm{4}{lnalnb} \\ $$