Greatest common Divisor of negative numbers To find gcd of negative numbers we can convert it to positive number and then find out the gcd. Will it make any difference?

It will not make any difference if $gcd(a,b) = d$ then $d \mid a$ and $d \mid b$ and if there exists another integer $c \mid a,b$ then $c \mid d$. Now , $d \mid -a,-b$ as well and if $c \mid -a,-b$ then $ c \mid d$ and so $$d = gcd(-a,-b) = gcd(-a,b) = gcd(a,-b) = gcd(a,b)$$
