I solved some of it but now I don't know if you continue it correctly ... To be performed: (lesson: Raducali of order "n")
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Answer:
[tex]( \sqrt[4]{7} + 2)( \sqrt[4]{7} - 2)( \sqrt[4]{7} + 4) \\ (first \: two \: is \: in \: the \: form \: of \: (x + y)(x - y) = {x}^{2} - {y}^{?} \\ then { \sqrt[4]{7} }^{2} - {2}^{2} \\ =( \sqrt{7} - 4) \\ so \: ( \sqrt{7} - 4)( \sqrt{7} + 4) \\ = { \sqrt{7} }^{2} - {4}^{2} \\ = 7 - 16 \\ = - 9 \\ thank \: you[/tex]