How do you know if y= x+x^2 is an even or odd function?

1 Answer
Dec 13, 2015

The function is neither even nor odd.

Explanation:

To test if the fuction is an even function, you would replace x with -x, and see if the resulting equation is the same as the original equation.

First, write out the original equation as a function by replacing y with f(x):

f(x) = x + x^2

Second, replace x with -x:

f(-x) = -x + (-x)^2

Third, simplify the equation:

f(-x) = -x + x^2

Finally, compare it to the original equation:

f(x) = x + x^2 \ != \ f(-x) = -x + x^2

Since f(x) != f(-x), the function is not even.

To test if the fuction is an odd function, you would test to see if f(-x) = -f(x). If the two equations are the same, then the function is odd.

First, write out the original equation as a function by replacing y with f(x):

f(x) = x + x^2

Second, multiply both sides of the equation by -1:

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

Third, simplify the equation:

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

Finally, compare it to the equation from our even function test:

f(-x) = -x + x^2 \ != \ -f(x) = -x - x^2

Since f(-x) != -f(x), the function is not odd.

If the function is not odd or even, then it is neither.