Prove gcd or disprove

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I want to know how to prove or disprove:

  1. For all integers $a, b$, we have $\text{gcd}(a,b)\le\min(a,b)$
  2. For all integers $a, b$, we have $\text{gcd}(a,b)\le\min(|a|,|b|)$
  3. For all non-zero integers $a, b$, we have $\text{gcd}(a,b)\le\min(|a|,|b|)$.

This is everything I want to know. Thank you.