$\log ab - \log |b| = $
$\log a$
$\log |a|$
$ - \log a$
None of these
If $A = {\log _2}{\log _2}{\log _4}256 + 2{\log _{\sqrt 2 \,}}\,2,$ then $A$ is equal to
The value of ${(0.05)^{{{\log }_{_{\sqrt {20} }}}(0.1 + 0.01 + 0.001 + ......)}}$ is
If $\log x:\log y:\log z = (y - z)\,:\,(z - x):(x - y)$ then
If ${a^2} + 4{b^2} = 12ab,$ then $\log (a + 2b)$ is
The number of solution $(s)$ of the equation $log_7(2^x -1) + log_7(2^x -7) = 1$, is -