Which is the value of this expression when [tex]$j = -2$[/tex] and [tex]$k = -1$[/tex]?

[tex]
\left(\frac{j k^{-2}}{j^{-1} k^{-3}}\right)^3
[/tex]

A. [tex]-64[/tex]

B. [tex]-\frac{1}{2}[/tex]

C. [tex]\frac{1}{2}[/tex]

D. [tex]64[/tex]



Answer :

To determine the value of the given expression when [tex]\( j = -2 \)[/tex] and [tex]\( k = -1 \)[/tex], we'll evaluate it step by step. The expression is:

[tex]\[ \left(\frac{j k^{-2}}{j^{-1} k^{-3}}\right)^3 \][/tex]

First, let's compute the inner fraction.

1. Calculate [tex]\( j k^{-2} \)[/tex]:
[tex]\[ j = -2, \quad k^{-2} = (-1)^{-2} = 1 \][/tex]
[tex]\[ j k^{-2} = -2 \times 1 = -2 \][/tex]

2. Calculate [tex]\( j^{-1} \)[/tex] and [tex]\( k^{-3} \)[/tex]:
[tex]\[ j^{-1} = (-2)^{-1} = -\frac{1}{2} \][/tex]
[tex]\[ k^{-3} = (-1)^{-3} = -1 \][/tex]
[tex]\[ j^{-1} k^{-3} = -\frac{1}{2} \times -1 = \frac{1}{2} \][/tex]

3. Calculate the inner fraction [tex]\( \frac{j k^{-2}}{j^{-1} k^{-3}} \)[/tex]:
[tex]\[ \frac{j k^{-2}}{j^{-1} k^{-3}} = \frac{-2}{\frac{1}{2}} = -2 \times 2 = -4 \][/tex]

4. Raise the result to the power of 3:
[tex]\[ (-4)^3 = -4 \times -4 \times -4 = -64 \][/tex]

Thus, the value of the expression [tex]\(\left(\frac{j k^{-2}}{j^{-1} k^{-3}}\right)^3\)[/tex] when [tex]\( j = -2 \)[/tex] and [tex]\( k = -1 \)[/tex] is:
[tex]\[ \boxed{-64} \][/tex]