If logx 64 = 3, then \(64 = x^3\)

\(4^3 = x^3\)

Since the indices are equal,

x = 4

Hence, x log\(_2\)8 

= 4(3.log\(_2\)2)

= where log\(_2\)2 = 1(1)

= 12 X 1 

= 12