# How to prove that one of $2,3,6$ is a square modulo every prime $p$? [duplicate]

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How to prove that one of $$2,3,6$$ is a square modulo every prime $$p$$?

I am thinking in terms of quadratic reciprocity but not getting any clue.

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## 1 Answer

what is $$(2|p) (3|p)(6|p) \; ?$$

• Ohh ok $(6|p)=(2|p)(3|p)$ if $p \neq 2,3$ then it is always $1$. Thanks – Gimgim Feb 1 at 4:55