What happens to fourier transform of the sampled output of pure sinusoidal input of 26kHz if sampled with 44.1kHz sample frequency?

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Because pure sinusoidal signal only contains impulses, I was wondering what happens to the fourier transform of the sample output from the sinusoidal input of $26$kHz if the sampling is done with sample frequency of $44.1$kHz.

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Because the sampling rate is less than two samples per cycle, the input will be aliased down to $26-44.1=-18.1$ kHz. If the wave is a sine wave, the minus sign just inverts the signal. If $t$ is a multiple of $1/(44.1$ kHz), $\sin (2\pi t 26$ kHz$)=\sin (-2\pi t 18.1$ kHz). If you have a large duration, you will see (almost all the) energy in frequencies near to $-18.1$ kHz. If you don't have an integral number of cycles, the discontinuity between the start and end of the interval will make other artifacts.