the question is 4/(^{4}√64m^{4}n^{2})

the given answer is

(^{4}√4n^{2}) / 2mn

but I get 4(^{4}√n^{2})/ 2mn

^{4}√ = root with 'index=4'

*the index 4 root is for the all

-( 64m^{4}n^{2})

-(4n^{2})

-(n^{2})

I'm not good at writing mathematics symbols sorry. help please SOS