8=2³
125=5³
64=4³
8^(2/3)+125^(1/3)-64^(1/3)= (2³)^2/3+(5³)^1/3-(4³)^1/3= 2^(3*2/3)+5^(3*1/3)-4^(3*1/3)= 2²+5¹-4¹=4+5-4=5
ответ:5
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