What kind of periodic signals cannot be represented with the Fourier Series?

1. Which of the following Cannot be the Fourier series of a periodic signal?
2. Which function Cannot be expressed as Fourier series?
3. Which of the following a Fourier series Cannot be defined?
4. Can any periodic function be represented by Fourier series?

Which of the following Cannot be the Fourier series of a periodic signal?

Which of the following cannot be the Fourier series expansion of a periodic signal? Explanation: x₁(t) = 2 cost + 3 cost is periodic signal with fundamental frequency w₀ = 1.

Which function Cannot be expressed as Fourier series?

So, x(t) is a periodic or not periodic. Since function in (b) is non periodic. So does not satisfy Dirichlet conditionand cannot be expanded in Fourier series.

Which of the following a Fourier series Cannot be defined?

Fourier series is defined for periodic function and constant. Fourier series can't be defined for non-periodic functions.

Can any periodic function be represented by Fourier series?

Yes it is. Fourier series is used to represent any function in terms of a periodic function that is in terms of sines and cosines.