Odd, Even, or Neither: Combining Functions in Algebra

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The discussion focuses on determining the outcomes of combining two functions, one even and one odd, through various arithmetic operations. It clarifies that the sum and difference of these functions will result in a function that is neither even nor odd. In contrast, the product and quotient of an even and an odd function yield an odd function. The conversation emphasizes the importance of correctly applying the definitions of even and odd functions in these combinations. Ultimately, the key takeaway is that only the product and quotient produce odd functions, while the sum and difference do not yield even or odd results.
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Homework Statement



Consider two functions, either of which is even or odd. But neither is neither even nor odd. Determine which algebraic combinations(sum, difference, quotient, product) of the given functions will result in an odd function, an even function, and in a function that is neither even nor odd.

Homework Equations



f(-x)=f(x) for even and f(-x)=g(x) for odd.

The Attempt at a Solution



I don't know how to unravel the logic. Say I pick the first function, it could be even or odd. But it is not (not even and not odd)=even or odd. So it must be even or odd? What is the point in all this? Are we not back at the starting point?
 
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I think you're getting caught up in the wording, it's basically asking you to pick combinations of even and odd functions and describe their output composed with various operators.

Even - Even
Odd - Odd
Odd - Even
Even -Odd
 
torquerotates said:

Homework Statement



Consider two functions, either of which is even or odd. But neither is neither even nor odd. Determine which algebraic combinations(sum, difference, quotient, product) of the given functions will result in an odd function, an even function, and in a function that is neither even nor odd.
The wording in the second sentence is unwieldy. The two functions are either even or odd. You don't have to consider any functions that don't fall into one of these categories.
torquerotates said:

Homework Equations



f(-x)=f(x) for even and f(-x)=g(x) for odd.
Your definition for an odd function is incorrect. What's the correct definition?
torquerotates said:

The Attempt at a Solution



I don't know how to unravel the logic. Say I pick the first function, it could be even or odd. But it is not (not even and not odd)=even or odd. So it must be even or odd? What is the point in all this? Are we not back at the starting point?

Consider one arithmetic operation at a time. Call the functions e and o. As Student100 says, look at the four possible combinations and say whether the sum is even, odd, or neither.

Do the same thing for each of the remaining three arithmetic operations.
 
Thanks, I was tired, f(-x)=-f(x) for odd.

product(-x)=e(-x)o(-x)=(e(x))(-o(x))=-e(x)o(x)=-product(x) =>product(x) is odd

quotient(-x)=e(-x)/o(-x)=e(x)/(-o(x))=-e(x)/o(x)=-quotient(x) => quotient(x) is odd.

The sum and difference gives us neither.

There is nothing that can give an even.
 
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