- #1
C0nfused
- 139
- 0
Hi everybody,
How do we define positive and negative numbers? Also, how do we prove that (-a)(-b)=ab and also that if a<b then ac<bc for c>0 and ac>bc for c<0 ?
Thanks
How do we define positive and negative numbers? Also, how do we prove that (-a)(-b)=ab and also that if a<b then ac<bc for c>0 and ac>bc for c<0 ?
Thanks