F-BF Identifying Even and Odd Functions

Alignments to Content Standards: F-BF.B.3


Determine whether each of these functions is odd, even, or neither. Use algebraic methods on all of the functions. You may start out by looking at a graph, if you need to.

  1. $f(x) = 3^x + 3^{-x}$
  2. $g(x) = 2^x – 2^{-x}$
  3. $h(x) = x^2 + 4x - 2$
  4. $j(x) = x^3 – 4x$

IM Commentary

This task includes an experimental GeoGebra worksheet, with the intent that instructors might use it to more interactively demonstrate the relevant content material. The file should be considered a draft version, and feedback on it in the comment section is highly encouraged, both in terms of suggestions for improvement and for ideas on using it effectively. The file can be run via the free online application GeoGebra, or run locally if GeoGebra has been installed on a computer.

Attached Resources

  • Geogebra file for task
  • Solution

    1. $f(x)$ is even since $f(-x) = 3^{-x} + 3^x = f(x)$.
    2. $g(x)$ is odd since $g(-x) = 2^{-x} – 2^x = -g(x)$.
    3. $h(x)$ is neither odd nor even since $h(-x)$ equals neither $h(x)$ nor $-h(x)$.
    4. $j(x)$ is also odd, since $j(-x)=(-x)^3-4(-x) = -(x^3)+4x=-j(x)$.

    rhill says:

    almost 3 years

    Where do I find the "show attached resources" link. Thanks.

    Cam says:

    over 2 years

    Our apologies -- we're working on correcting a bug which removed all of the attached resources. Hopefully they will all be back soon (after which the link should be pretty apparent).

    Cam says:

    over 2 years


    Cam says:

    over 2 years

    Problem solved. You can now find the attached resource(s) right above the Solutions pane. Apologes again for the mix-up.

    Marianne Springer says:

    over 3 years

    How do I access the experimental geogebra worksheet file?

    Kristin says:

    over 3 years

    Sorry--we forgot to make it visible. Now it should show up under the "Show attached resources" link.