Are trig functions polynomial fuctions?

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Homework Help Overview

The discussion revolves around whether the expression 3cos(22x) + cos(x^2) - 1 qualifies as a polynomial function. Participants are exploring the definitions and characteristics of polynomial functions in relation to trigonometric expressions.

Discussion Character

  • Conceptual clarification, Assumption checking

Approaches and Questions Raised

  • Some participants question the definition of a polynomial function and whether trigonometric functions can be classified as polynomials. Others suggest that the expression can be rearranged into a quartic form in terms of cos(x), but note that it may not be a polynomial in x unless infinite degree polynomials are considered.

Discussion Status

The discussion is ongoing, with participants raising questions about the nature of polynomial functions and their relationship to trigonometric functions. There is no explicit consensus yet, but various interpretations are being explored.

Contextual Notes

Participants have noted the lack of clarity in the original poster's understanding of the question, which may affect the direction of the discussion.

zeion
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Homework Statement



Is 3cos22x + cosx2 - 1 a polynomial function?


Homework Equations





The Attempt at a Solution

 
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zeion said:

Homework Statement



Is 3cos22x + cosx2 - 1 a polynomial function?


Homework Equations





The Attempt at a Solution


What is the definition of "a polynomial function"?
 
Well, this function can be arranged to a quartic in cos(x). As a polynomial in x, however, it's only a polynomial if you allow polynomials of infinite degree.
 
And so, the OP gets a free answer with no attempt at the solution and no indication that he even understands the question. :rolleyes:
 
stevenb said:
And so, the OP gets a free answer with no attempt at the solution and no indication that he even understands the question. :rolleyes:

Agh, my bad my bad. Think I should delete or has he already seen it?
 
Char. Limit said:
Agh, my bad my bad. Think I should delete or has he already seen it?

:wink: Well, it happened on your 1000th post, so you earned a get out of jail free card, and we have to let it go.
 
I already saw it HAHAHA
 

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