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I am a retired physician scientist. I am currently writing a research paper describing how cell groups within the thalamic nucleus of the brain are organized. I need to insert equations into the document I am going to create and I cannot remember how. I remember that there are palettes of mathematical symbols which may be accessed. Unfortunately, I cannot remember how to access these palettes, nor can I figure out how to access them from the help or demonstration sections of wolfram software. So I need help. Thanks.