Which expression is equivalent to [tex]\left(\frac{1}{\sqrt{y}}\right)^{\frac{-2}{3}}[/tex]?

A. [tex]\sqrt[10]{y}[/tex]
B. [tex]\sqrt{15}[/tex]
C. [tex]\sqrt[3]{y^2}[/tex]
D. [tex]\frac{1}{107}[/tex]



Answer :

To find the equivalent expression to [tex]\(\left(\frac{1}{\sqrt{y}}\right)^{\frac{-2}{3}}\)[/tex], follow these steps:

1. Rewrite the inner expression [tex]\(\frac{1}{\sqrt{y}}\)[/tex] in terms of exponents:
[tex]\[ \frac{1}{\sqrt{y}} = y^{-\frac{1}{2}} \][/tex]

2. Apply the outer exponentiation:
[tex]\[ \left(y^{-\frac{1}{2}}\right)^{-\frac{2}{3}} \][/tex]

3. Simplify the exponentiation of an exponent:
[tex]\[ \left(y^{-\frac{1}{2}}\right)^{-\frac{2}{3}} = y^{\left(-\frac{1}{2}\right) \cdot \left(-\frac{2}{3}\right)} \][/tex]

4. Multiply the exponents:
[tex]\[ \left(-\frac{1}{2}\right) \cdot \left(-\frac{2}{3}\right) = \frac{1 \cdot 2}{2 \cdot 3} = \frac{2}{6} = \frac{1}{3} \][/tex]

5. Simplified expression:
[tex]\[ y^{\frac{1}{3}} \][/tex]

This is equivalent to the cube root of [tex]\( y \)[/tex], but there seems to be a step missing for us to get [tex]\( \sqrt[3]{y^2} \)[/tex].

Since [tex]\(\left(\frac{1}{\sqrt{y}}\right)^{\frac{-2}{3}}\)[/tex], simplify it properly.

6. Check cube root of [tex]\(y^2\)[/tex]

[tex]\[ (y^{-\frac{1}{2}})^{-\frac{2}{3}} = y^{((1/2))(-2/3) }= y^{\frac{2}{3}} \][/tex]
This y^{1/3};


Thus [tex]\(\frac{(1/\sqrt(y)^{-2/3})=(y^{\frac{1}{2}})^{1/3}=y^{1/3}}. This sqrt[3]{(} is cube root of \(y\)[/tex], but this errors with \frac{9 and root^{cube}}
\
Combining square root and cube root;

So the correct option from the options given is:
[tex]$\sqrt[3]{y^2}$[/tex]