Respuesta :

Answer:

We conclude that:

[tex]\left(9c^{-9}\right)^{-3}=\frac{c^{27}}{729}[/tex]

Step-by-step explanation:

Given the expression

[tex]\left(9c^{-9}\right)^{-3}[/tex]

Apply exponent rule:   [tex]a^{-b}=\frac{1}{a^b}[/tex]

[tex]\left(9c^{-9}\right)^{-3}=\frac{1}{\left(9c^{-9}\right)^3}[/tex]

Let us first solve:

[tex]\left(9c^{-9}\right)^3[/tex]

Apply exponent rule:  [tex]\left(a\cdot \:b\right)^n=a^nb^n[/tex]

[tex]\left(9c^{-9}\right)^3=9^3\left(c^{-9}\right)^3[/tex]

             [tex]=729\left(c^{-9}\right)^3[/tex]

Apply exponent rule:   [tex]\left(a^b\right)^c=a^{bc},\:\quad \mathrm{\:assuming\:}a\ge 0[/tex]

             [tex]=729c^{-9\cdot \:3}[/tex]

             [tex]=729c^{-27}[/tex]

Apply exponent rule:   [tex]a^{-b}=\frac{1}{a^b}[/tex]

             [tex]=729\cdot \frac{1}{c^{27}}[/tex]

             [tex]=\frac{729}{c^{27}}[/tex]

Therefore, the expression [tex]\left(9c^{-9}\right)^{-3}=\frac{1}{\left(9c^{-9}\right)^3}[/tex] becomes

[tex]\left(9c^{-9}\right)^{-3}=\frac{1}{\left(9c^{-9}\right)^3}[/tex]

               [tex]=\frac{1}{\frac{729}{c^{27}}}[/tex]         ∵  [tex]\left(9c^{-9}\right)^3=\frac{729}{c^{27}}[/tex]

               [tex]=\frac{c^{27}}{729}[/tex]          ∵  [tex]\frac{1}{\frac{b}{c}}=\frac{c}{b}[/tex]

Hence, we conclude that:

[tex]\left(9c^{-9}\right)^{-3}=\frac{c^{27}}{729}[/tex]

Answer:

b

Step-by-step explanation: