\sqrt[3]{abc}=4 i (abcd)^{\frac{1}{4}}=2\sqrt{10}
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\sqrt[3]{abc}=4
(abc)^{\frac{1}{3}}=4 \ |^3
abc=4^3
abc=64
podstawiam
(abcd)^{\frac{1}{4}}=2\sqrt{10}
(64\cdot d)^{\frac{1}{4}}=2\sqrt{10} \ |^4
64d=2^4\cdot (10^{\frac{1}{2}})^4
64d=16\cdot 10^{\frac{4}{2}} \ |:16
4d=10^2
4d=100 \ |:4
d=25