$$[ \frac { 8 } { 9 } ] ^ { - 4 } \times [ \frac { 8 } { 9 } ] ^ { - 2 } = \frac { 8 ^ { 3 x } } { 9 }$$
$x=\frac{14\log_{2}\left(3\right)}{9}-2\approx 0.465497223$
$x=\frac{2\pi n_{1}i}{9\ln(2)}+\frac{14\log_{2}\left(3\right)}{9}-2$
$n_{1}\in \mathrm{Z}$
