Solution
= Solution
At $x=1$, the <natural logarithm> has value zero and <derivative> $1/x=1$. Its <tangent line> is therefore
$$
\boxed{y=x-1.}
$$
= Solution
At $x=1$, the <natural logarithm> has value zero and <derivative> $1/x=1$. Its <tangent line> is therefore
$$
\boxed{y=x-1.}
$$