If $${\log _7}2 = \lambda $$, then the value of $${\log _{49}}(28)$$ is

The sequence log a, $$\log {{{a^2}} \over b}$$, $$\log {{{a^3}} \over {{b^2}}}$$, ...... is

If $$\left(x^2 \log _x 27\right) \cdot \log _9 x=x+4$$ then the value of $$x$$ is

If x satisfies the inequality $${\log _{25}}{x^2} + {({\log _5}x)^2} < 2$$, then x belongs to