38: The graphs intersect when
ln(x) = (1 − x)/x.
This equation is not solvable agebraically, but we can guess one solution:
x = 1. Since the graphs of both functions are
strictly monotone for
x > 0, there is no other interection.
Slopes of tangent lines are given by the derivative. For the above
point one should get
![](gif4/ecc4fc2.gif)
How do you recognize whether the slopes are perpendicular?
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