2.Simplify the given expression to rational exponent form, justify each step by identifying the properties of rational exponents used. All work must be shown.
\[\frac{1}{\sqrt[3]{x^{-6}}}\]
@AravindG can you help explain how he got it
I thought you wanted to understand how to simplify the expression.
Its same as question?
@deezgurls, do you want an explanation of how to simplify the expression?
Yeah, I don't know how to simplify it D: Sorry for the hassle
So first, understand the rule \[x^{-a} = \frac{1}{x^a}\] \(x^{-a}\) can be read as the "inverse of x to the a".
In other words, the negative exponent means "inverse".
Okay
So the first property so apply is "inverse property of exponents", which after application we get: \[\dfrac{1}{\sqrt[3]{\dfrac{1}{x^6}}}\]
From here, there are a few different rules we can use. First of all understand that \[\sqrt[3]{1^3} = 1\] \[\sqrt[6]{1^6} = 1\]
Actually let's do this, rewrite the fraction as: \[\dfrac{1}{\dfrac{\sqrt[3]{1}}{\sqrt[3]{x^6}}}\] We can do that by way of the following rule: \[\sqrt[n]{\dfrac{a}{b}} = \dfrac{\sqrt[n]{a}}{\sqrt[n]{b}}\]
okay, I wrote it down
Next, we simplify the numerator of the inner fraction according to the rule above to get: \[\dfrac{1}{\dfrac{1}{\sqrt[3]{x^6}}}\]
okay
There's another rule we can utilize to attempt to simplify further: \[x^{ab} = (x^{a})^b\] In this case: \[x^6 = x^{(2)(3)} = (x^2)^3\]
Alright
So we can re-write the fraction as: \[\dfrac{1}{\dfrac{1}{\sqrt[3]{(x^2)^3}}}\]
And we see yet another rule we can use. In general: \[\large\sqrt[n]{x^n} = x\]
The root and exponent cancel if they have the same base.
This is because \[\large\sqrt[n]{x^n} = x^{\frac{n}{n}} = x^1 = x\]
So now we have just: \[\dfrac{1}{\dfrac{1}{x^2}}\] Which can be re-written as : \[1 \div \frac{1}{x^2}\] We can do this by way of the definition of division: \[\frac{a}{b} = a \div b\]
Finally, we have the reciprocal rule, which utliizes the fact that division is merely the inverse of multiplication. In other words: \[a \div b = a \times \frac{1}{b}\] So we have: \[1 \div \frac{1}{x^2} = 1 \times x^2\]
In other words, the final result is just \[x^2\]
so the answer is x2?
okay now i'm confused
Basically, negative exponent doesn't mean the answer will be negative.
Remember, negative exponent means "inverse"
Also, remember, that we had to reduce the expression. And we used the rules of exponents and algebra to do so.
Alright, thank you so much!
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