how do you show this converges to 1

for hours now i try to solve this but i don't find any way to show this

i tried some rewritting with n-1 and n+1 i tried some logarithm etc but non of it works.
this would be so easy if it just was (n)^(1/n) or (n^2)^(1/n) or if it was some x^n type stuff
but this single -n makes this impossible to solve for me