Fractional Exponents (How is it done?)

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Discussion Overview

The discussion revolves around the manipulation and understanding of fractional exponents, specifically how to express and simplify expressions like 2^(5/2). Participants explore the rules of exponents, the interpretation of fractional powers, and the confusion arising from notation.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • One participant questions how 2^(5/2) can be expressed as 2^2 multiplied by 2^(1/2), expressing confusion over the factorization process.
  • Another participant proposes the rule that x^(a+b) = (x^a)(x^b) for natural numbers, seeking agreement on this principle.
  • A participant expresses uncertainty about the values of a and b in the context of fractional exponents, attempting to relate them to 2^(5/2) but acknowledges potential errors in their reasoning.
  • Discussion includes examples of integer exponents, such as 2^4 = 2^2 * 2^2, to illustrate the multiplication of powers.
  • One participant reflects on the addition of fractional exponents, suggesting that 2^2 and 2^(1/2) could combine to form 2^(5/2), but questions the necessity of fractional exponents in this context.
  • Another participant points out the ambiguity in the notation 2^5/2, suggesting it could be misinterpreted as (2^5)/2 and recommends clearer formatting using LaTeX.
  • A later reply clarifies how to split the exponent 5/2 into 4/2 + 1/2, demonstrating the application of exponent rules.

Areas of Agreement / Disagreement

Participants express varying levels of understanding regarding fractional exponents, with some agreeing on basic exponent rules while others remain confused about specific applications and notations. The discussion does not reach a consensus on the best way to express or interpret fractional exponents.

Contextual Notes

There are limitations in the clarity of notation used, particularly with the expression 2^5/2, which could lead to different interpretations. The discussion reflects a range of assumptions and interpretations regarding the rules of exponents and their application to fractional values.

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How does 2^5/2 become 2^2 multiplied by 2^1/2?
(The '^' means 'to the power of' so 2 to the power of 5/2. I am not sure how to write this as an exponent as this is my first post.)

2^5/2 = 2^2 × 2^1/2

So 2^2 = 4 and 2^1/2 means Square Root so there is a radical sign, so it becomes √2.

I tried to reverse engineer the solution but I'm still not sure how 2^5/2 makes it. I know you first Square root it so √2 then you put to the power of 5 so √2^5. This goes into decimals so I am confused on what to do next. I looked at the solution and I can see that both of them make 2^5/2 I just don't know how it was factorized into those specific numbers, because 4 x √2 = 4√2 and somehow that is √2^5? I know 2^5 also makes 32.

So I think I might of done something wrong or I don't know the correct method, can someone please attempt to help me and thank you for your time!
 
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Do you agree that x^(a+b)=(x^a) (x^b) for natural x,a,b?

edit, forgot a +
 
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In my case would that be 2^5/2 (5 is a and 2 is b) = (2^5) (5^2)? I'm quite sure I'm doing something wrong so I think I can't agree on that even though I think its correct.

So what is a and b? If a and b are 5 and 2 they make (2^5) (5^2) making 800. I am kind of lost... Am I getting it wrong?

Another go at it I see that 2^5 = 32 and 5^2 = 25 - So do I put in the fraction making it 2^5/1 and 5^1/2?

Oh now I see it and the '+', Thank you for changing it
 
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Do you agree that
2^4 = 2^2 * 2^2
3^{10}=3^4 * 3^6
 
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Yes, Because when you are multiplying powers you add them together, but since I started fractional exponents I am very confused - probably because of the fractions.

So if you added 2^2 and 2^1/2 that would make 2^3/2 if i am correct or 2.5?

Okay so there's 2/1 + 1/2 = 2 5/2
So adding fractions you double it to make it 4/2 then add it to make it 5/2 making it 2^5/2.
So we done this backwards but how did 2^5/2 split up to make those 2?

Oh wait (Edit), So you could also spilt it up to something else? But it has to be a Fractional Exponents because so it can be combined? Not sure why it has to be a fractional exponent but I know you split the expression into the product of an integer exponent and the factor with a fractional coefficient less than one. I think the reason why this is done is so you can keep the root in the equation, otherwise it no longer has a fractional exponent.

Thank you for your valuable time, which you were very helpful!

PS. If I made any mistakes please correct (:
 
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2+\frac{1}{2}=\frac{4}{2}+\frac{1}{2}=\frac{5}{2}
 
2^5/2 is problematic, it could mean ##\frac{2^5}{2}##. You can write it as 2^(5/2) or better [noparse]25/2[/noparse], which gets parsed as 25/2. And you can use LaTeX here.

You can split up the 5/2 like this:
$$\frac{5}{2}=\frac{4+1}{2}=\frac{4}{2}+\frac{1}{2}=2+\frac{1}{2}$$
And then use the rule for exponents written above.
 

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