Find out the value?

Sol: ​    √1/ √x      ​=   ​3
      ​=> Squaring both sides we get
 
      =>    ​(√1/ √x)²     ​=   ​3²
      ​=>    1 /√x              =    9
      ​=>    ​√x                  ​=   ​1/9
Squaring both sides we get
                 X                  = 1/ 81

Hence option B is the correct answer.