Someone please explain Rational Exponents, (please be descriptive)
\[x^{\frac{a}{b}} = \sqrt[b]{a}\]
\[b \neq 0\]
I want to find out an easy way to simplify working out rational exponents given an exponent within the root of a number (Example: 4^sqrt300 = n). Too many sources show how exponents from roots can be broken into fractional exponents of the rooted number, but what's the work needed to just get the answer????
@JoãoVitorMC That is very very wrong.
@MOJUTMNT You want a method of calculating rational numbers?
Yes. ^~^
yes sorry i missed the "x" \[x^{\frac{a}{b}} = \sqrt[b]{x^a}\]
Through roots.
Okay, the first thing you should do is simplify the fraction to the simplest form to make your life easy. Then do this: \[ c^{a/b} = (c^a)^{1/b} \]Now, to make things easier we'll say \(x = c^a\) and use \(x\) from here on out. I suppose it wouldn't be hard for you to find \(x\), right?
We want to find \(x^{1/b}\)
Do you understand how it doesn't really matter what the numerator is, that the hard part is really just in the denominator?
Before you continue, this is done through square roots.
Can you give an example of what you mean?
For instance, I mean like the square root of 300 with an exponent of 4 next to the root.
\[ \sqrt{300^4} \]?
With the 4 to the left of the square root as an exponent.
\[ \sqrt[4]{300} \]?
Yes.
Do you know how to factor out a number?
Do you mean by finding the highest number divisible?
Factorizing a number... Here's an example: |dw:1363575345150:dw|
So I have to find the lowest number divisible, and then break it down by repeating that same process?
You want to divide out any prime numbers, until all that is left is a bunch of prime numbers.
This is perfect, can I show you an example of a problem I have?
|dw:1363575958150:dw|
Where does the exponent of 4 come into play?
There is no exponent of 4, that's multiplication\[135 = 5 *3 *3 *3 = 5* 3^3 \] so now your \[\large 4 * \sqrt[3]{135} \] \[\huge 4 * \sqrt[3]{5*3^3}\]
\[\large 4 * \sqrt[3]{5*3^3} = 4 * \sqrt[3]{5}*\sqrt[3]{3^3}\]
No, the four is an exponent... just like the 3 is in the new problem you just created.
I didn't create a problem... i was using your image: http://assets.openstudy.com/updates/attachments/51467a27e4b04cdfc582af15-mojutmnt-1363575901148-rationalexponent.png
My fault. That question was meant for the previous problem.
Before we continue can you show me how the exponent of 4 was used in the previous problem.
maybe a helpful hint, exponents can be written multiple ways ex. these are equivalent \[\sqrt[4]{x}=x^{\frac{ 1 }{ 4 }}\]
was that the square root to fraction, you were looking for?
Oops, my bad, 300 = 3*2*2*5*5 NOT 2*2*5*5*5 If you understand up to here, then... \[\large (3*2^2*5^2)^{\frac{ 1 }{ 4 }} = 3^{\frac{ 1 }{4 }} (2^2)^{\frac{ 1 }{ 4 }} * (5^2)^{\frac{ 1 }{ 4}}\]
Thank you very much for that answer. Thank you all for being descriptive. All I needed was for someone to spell it out for me.
@agent0smith is that the final answer?
Not yet. Can you simplify it from there? Note that \[\huge (a^b)^c = a ^{b*c}\] try using it on this: \[\large 3^{\frac{ 1 }{4 }} *(2^2)^{\frac{ 1 }{ 4 }} * (5^2)^{\frac{ 1 }{ 4}}\]
Yes I can, thank you. Now back to the next question I will post a new screen shot.
This was Q2:\[ \large 4 * \sqrt[3]{5*3^3} = 4 * \sqrt[3]{5}*\sqrt[3]{3^3} \] \[\large 4 * \sqrt[3]{5}*({3^3})^{\frac{ 1 }{3 }}\]
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