What is the answer to this question. 8 to the power of minus an eighth

8^-1/8  =  1 / 8^1/8

         =  1 / (2³)^1/8

         =  1 / 2^3/8

         =  [ 1 · 2^5/8 ] / [ 2^3/8 · 2^5/8 ]

        =   2^5/8 /  2

        =  ½ ·  2^5/8 

        =  0.7711054127 ...

 

[I'm not sure what form you want ...]