Could anyone help me with these questions?:
Prove that there exists a unique real number x such that ln x = 2
&
Let a and b be non zero integers. Prove that a divides b and b divides a if and only if a = +/- b
1) $\displaystyle ln x = 2 , $ is $\displaystyle e^{2} = x $
2)if a divides b then b = ak for some integer k, if b divides a, then a = bm for some integer m, so b = bmk, so mk = 1, since m and k are integers, either both m and k are -1, or both are positive 1. so either m = 1 so a = b or m = -1 and a = -b