The value of $\sqrt {(\log _{0.5}^24)} $ is
$-2$
$\sqrt {( - 4)} $
$2$
None of these
The value of ${\log _3}\,4{\log _4}\,5{\log _5}\,6{\log _6}\,7{\log _7}\,8{\log _8}\,9$ is
The number ${\log _{20}}3$ lies in
If ${\log _{10}}x + {\log _{10}}\,y = 2$ then the smallest possible value of $(x + y)$ is
If $x = {\log _a}(bc),y = {\log _b}(ca),z = {\log _c}(ab),$then which of the following is equal to $1$
For $y = {\log _a}x$ to be defined $'a'$ must be