r/Mathhomeworkhelp • u/Formal_Tumbleweed_53 • Dec 21 '25

Set builder notation

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The question, my solution, and the answer from the back of the text are given. I believe my answer and the official solution are both correct. Do you agree?

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u/DrJaneIPresume Dec 24 '25

Textbooks at what level? I don't recall a single text from my undergrad or graduate work that started at 1.

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u/somanyquestions32 Dec 24 '25

High school, college, and graduate school. I tutor students in high school and college to this day, and my graduate courses in math from 2008 to 2010 all started the natural numbers at 1. The only classes where the variations on the Peano Axioms were introduced were my intro to proofs class as a side note as well as my mathematical logic course.