Can a cell exist without a nucleus?

Red blood cells, platelets, for example, do not have nuclei, although mammals are composed of eukaryotic cells. So, maybe, but with special functions, like red blood cells, the absence of a nucleus should be justified.

Remember: The process of learning a person lasts a lifetime. The value of the same knowledge for different people may be different, it is determined by their individual characteristics and needs. Therefore, knowledge is always needed at any age and position.