Use the formulas here:
http://www.math10.com/en/algebra/logari ... ln-lg.html1) use the formula: [tex]log_bc = log_ac / log_ab[/tex]
and make all logarithms bases 2
log<sub>1/2</sub>(x-1) = log<sub>2</sub>(x-1) / log<sub>2</sub>(1/2)
[tex]1/2 = 2^{-1}[/tex] so [tex]log_2(1/2) = log_2(2^{-1}) = -1[/tex]
then we have:
[tex]-log_2(x-1) - log_2(x+1) + 2log_2(7 - x) = 1[/tex]
and we will use the formula: log<sub>a</sub>(b.c) = log<sub>a</sub>b + log<sub>a</sub>c
so: [tex]-( log_2(x-1)(x+1) ) = -(2log_2(7 - x)-1)[/tex]
[tex]1 = log_22[/tex]
and [tex]2log_2(7 - x) = log_2(7 - x)^2[/tex]
so: [tex]log_2(x-1)(x+1) = log_2((7 - x)^2/2)[/tex]
I think you do not need more help about this logarithmic equation