Which expression is equivalent to [tex]\left(\frac{4mn}{m^{-2} n^6}\right)^{-2}[/tex]? Assume [tex]m \neq 0[/tex], [tex]n \neq 0[/tex].

A. [tex]\frac{n^6}{16 m^8}[/tex]
B. [tex]\frac{n^{10}}{16 m^6}[/tex]
C. [tex]\frac{n^{10}}{8 m^8}[/tex]
D. [tex]\frac{4 m^3}{n^8}[/tex]



Answer :

To determine which expression is equivalent to [tex]\(\left(\frac{4 m n}{m^{-2} n^6}\right)^{-2}\)[/tex], we need to simplify the given expression step by step.

First, simplify the inner fraction:
[tex]\[ \frac{4 m n}{m^{-2} n^6} \][/tex]

Recall that [tex]\(m^{-2}\)[/tex] is the same as [tex]\(\frac{1}{m^2}\)[/tex]. So the expression becomes:
[tex]\[ \frac{4 m n}{\frac{1}{m^2} n^6} = 4 m n \cdot m^2 n^{-6} \][/tex]

Combine the exponents for like bases:
[tex]\[ = 4 m^{1+2} n^{1-6} = 4 m^3 n^{-5} \][/tex]

Now, raise this simplified expression to the power of [tex]\(-2\)[/tex]:
[tex]\[ \left(4 m^3 n^{-5}\right)^{-2} \][/tex]

This is the same as taking the reciprocal and raising it to the positive power of 2:
[tex]\[ = \frac{1}{\left(4 m^3 n^{-5}\right)^2} \][/tex]

Separate the terms within the parenthesis and raise each to the power of 2:
[tex]\[ = \frac{1}{4^2 \cdot (m^3)^2 \cdot (n^{-5})^2} \][/tex]

Calculate each exponentiated term:
[tex]\[ = \frac{1}{16 \cdot m^6 \cdot n^{-10}} \][/tex]

Simplify the negative exponent on [tex]\(n\)[/tex]:
[tex]\[ = \frac{1}{16 \cdot m^6} \cdot n^{10} = \frac{n^{10}}{16 m^6} \][/tex]

Therefore, the expression equivalent to [tex]\(\left(\frac{4 m n}{m^{-2} n^6}\right)^{-2}\)[/tex] is:
[tex]\[ \boxed{\frac{n^{10}}{16 m^6}} \][/tex]