Determine whether f is even, odd, or neither?

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Discussion Overview

The discussion revolves around determining whether specific functions are even, odd, or neither. It includes theoretical definitions and properties related to even and odd functions, as well as examples provided by participants.

Discussion Character

  • Technical explanation, Conceptual clarification, Homework-related

Main Points Raised

  • One participant requests help in determining the nature of four specific functions.
  • Another participant provides the definitions of even and odd functions, stating that f(-x) = f(x) indicates an even function, while f(-x) = -f(x) indicates an odd function.
  • A participant mentions that a rational function is even if all exponents of x are even and odd if all exponents of x are odd, noting that this is easy to prove.
  • It is pointed out that not all functions have exponents, with sine and cosine functions provided as examples of odd and even functions, respectively.
  • A later reply highlights the elegance of series expansions consisting of only odd-numbered or even-numbered polynomial terms for sine and cosine functions.

Areas of Agreement / Disagreement

Participants generally agree on the definitions of even and odd functions, but there is no consensus on the specific classification of the functions presented in the initial request.

Contextual Notes

The discussion does not resolve the classification of the specific functions mentioned, and the application of the definitions may depend on further analysis of each function.

akt223
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I've tried looking through my book to see how to do these, but I just can't find it. Any help would be appreciated:

1) f(x) = 2x^5 - 3x^2 +2

2) f(x) = x^3 - x^7

3) f(x) = (1-x^2)/(1+x^2)

4) f(x) = 1/(x+2)

Thanks in advance!
 
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the definition of an even and an odd function is as follows:

[tex]f(-x) = f(x)[/tex] is and even function and

[tex]f(-x) = -f(x)[/tex] is an odd function.
 
Alright, I think I get it, thanks.
 
It is also true (easy to prove) that a rational function (polynomial or quotient of polynomials) is even if and only if all exponents of x are even, odd if and only if all exponents of x are odd.

Of course, functions don't always have "exponents"! sin(x) is an odd function and cos(x) is an even function.
 
Of course, functions don't always have "exponents"! sin(x) is an odd function and cos(x) is an even function.

But the series expansions precisely consist of only odd-numbered and only even-numbered polynomial terms, respectively. It's quite elegant.
 

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