Square root of y^2 over y^21
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[tex] \looparrowright \sf \sqrt{ \dfrac{ {y}^{7} }{ {y}^{21} } } [/tex]
[tex] \\ \\ [/tex]
[tex] \looparrowright \sf \sqrt{ \dfrac{ {y}^{0} }{ {y}^{21 - 7} } } [/tex]
[tex] \\ \\ [/tex]
[tex] \looparrowright \sf \sqrt{ \dfrac{ {y}^{0} }{ {y}^{14} } } [/tex]
[tex] \\ \\ [/tex]
[tex] \looparrowright \sf \sqrt{ \dfrac{ 1}{ {y}^{14} } } [/tex]
[tex] \\ \\ [/tex]
[tex] \looparrowright \sf \dfrac{1}{ {y}^{7} } [/tex]