Which expression represents (fog) (x)

Step-by-step explanation:
[tex]f( \frac{x}{x - 1} ) = log( {( \frac{x}{x - 1} )}^{2} - 2( \frac{x}{x - 1}) ) \\ = log(\frac{ {x}^{2} }{ {(x - 1)}^{2} } -2\frac{x}{(x - 1)} ) \\ = log( \frac{ {x}^{2} - 2x(x - 1) }{ {(x - 1)}^{2} } ) [/tex]