Negative values for wavelengths and frequencies

[ayushibanerjee06]

In many of the questions I in the post-module assessment, when I solved for wavelength or frequency I would get the correct answer, but it was just negative. I know that wavelength and frequency should always be positive, so am I doing something wrong in my calculations? Or is it just a theoretical thing that I can't prove mathematically?

[Sarah Blake-2I]

When solving for frequency, you cannot have a negative E value, so we change it to positive. It is just a conceptual idea that you cannot have negative frequency or wavelength. :)

[ayushibanerjee06]

When solving for frequency, you cannot have a negative E value, so we change it to positive. It is just a conceptual idea that you cannot have negative frequency or wavelength. :)

That's what I thought. Thanks!