Under rather general conditions, a periodic function ƒ(x) can be expressed as a sum of sine waves or cosine waves in a Fourier series.

It is also well known that the integral of a sine wave or cosine wave over one or more full cycles is zero.

Monochromatic sources will give cosine waves in their interferograms.

Making the complex variable purely imaginary by putting in the Laplace transform means that the signal is again being analysed into just sine and cosine waves.

The other examples of continuous signals are sine wave, cosine wave, triangular wave etc.

The real part (cosine wave) is denoted by a solid line, and the imaginary part (sine wave) by a dashed line.

Informally, it reflects the difficulty inherent in approximating a discontinuous function by a finite series of continuous sine and cosine waves.

The slope of a sine wave is a cosine wave, which is the same shape as a cosine wave.

For a sine wave, this works out to be the opposite of a cosine wave.

A cosine wave begins at its maximum value due to it phase difference from the sinewave.