Which expression is equivalent to [tex]$x^{-\frac{5}{3}}$[/tex]?

A. [tex]\frac{1}{\sqrt[5]{x^3}}[/tex]
B. [tex]\frac{1}{\sqrt[3]{x^5}}[/tex]
C. [tex]-\sqrt[3]{x^5}[/tex]
D. [tex]-\sqrt[5]{x^3}[/tex]



Answer :

To determine which expression is equivalent to [tex]\( x^{-\frac{5}{3}} \)[/tex], let's simplify and analyze each option step-by-step.

### Step-by-Step Analysis

#### 1. Analyze [tex]\( x^{-\frac{5}{3}} \)[/tex]
This can be written as:
[tex]\[ x^{-\frac{5}{3}} = \frac{1}{x^{\frac{5}{3}}} \][/tex]

#### 2. Equivalent expressions:
We need to examine the given options to see which one matches the above simplification.

#### 3. Analyze Option 1: [tex]\( \frac{1}{\sqrt[5]{x^3}} \)[/tex]
[tex]\[ \frac{1}{\sqrt[5]{x^3}} = \frac{1}{x^{\frac{3}{5}}} \][/tex]

Since [tex]\( \frac{3}{5} \neq \frac{5}{3} \)[/tex], this option is not equivalent to [tex]\( x^{-\frac{5}{3}} \)[/tex].

#### 4. Analyze Option 2: [tex]\( \frac{1}{\sqrt[3]{x^5}} \)[/tex]
[tex]\[ \frac{1}{\sqrt[3]{x^5}} = \frac{1}{x^{\frac{5}{3}}} \][/tex]

This matches [tex]\( \frac{1}{x^{\frac{5}{3}}} \)[/tex], so this option is a potential equivalent.

#### 5. Analyze Option 3: [tex]\( -\sqrt[3]{x^5} \)[/tex]
[tex]\[ -\sqrt[3]{x^5} = -x^{\frac{5}{3}} \][/tex]

This does not include the negative exponent, so it is not equivalent to [tex]\( x^{-\frac{5}{3}} \)[/tex].

#### 6. Analyze Option 4: [tex]\( -\sqrt[5]{x^3} \)[/tex]
[tex]\[ -\sqrt[5]{x^3} = -x^{\frac{3}{5}} \][/tex]

Again, since [tex]\( \frac{3}{5} \neq \frac{5}{3} \)[/tex], and the expression should not have a negative sign, this option is not equivalent to [tex]\( x^{-\frac{5}{3}} \)[/tex].

### Conclusion

After analyzing each option, we find that the only expression equivalent to [tex]\( x^{-\frac{5}{3}} \)[/tex] is:
[tex]\[ \frac{1}{\sqrt[3]{x^5}} \][/tex]

Thus, the correct answer is:
[tex]\[ \boxed{\frac{1}{\sqrt[3]{x^5}}} \][/tex]