Simply using exponents .Then find the products .
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Answer:
[tex]\sqrt[7]{b^{15}}[/tex]
Step-by-step explanation:
=> [tex]b^2*\sqrt[7]{b}[/tex]
=> [tex]b^2*b^{1/7}[/tex]
Where bases are same, powers are to be added.
=> [tex]b^{2+(1/7)}[/tex]
=> [tex]b^ {14+1/7}[/tex]
=> [tex]b^{15/7}[/tex]
=> [tex]\sqrt[7]{b^{15}}[/tex]