MCQ
If ${\log _5}a.{\log _a}x = 2,$then $x$ is equal to
  • A
    $125$
  • B
    ${a^2}$
  • $25$
  • D
    None of these

Answer

Correct option: C.
$25$
c
(c) ${\log _5}a.{\log _a}x = 2$   $\Rightarrow $ ${\log _5}x = 2$

$ \Rightarrow $ $x = {5^2} = 25$.

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