16^1/2+64^2/3-(1/81)^-3/4
16^1/2+64^2/3-(1/81)^-3/4=
=V16+(64^1/3)^2-(81^1/4)^3=4+4^2-3^3=4+16-27=-7
16^1/2+64^2/3-(1/81)^-3/4=16^1/2+8^4/3-(81)^3/4=4+2^4-3^3=4+16-27=-7