Show that the line `x/a+y/b=1` touches the curve `y=b e^(-x/a)` at the point where it crosses the y-axis.

Explanation

The point, where the curves intersects the axis of `Y` i.e. `x=0`
$$ \therefore \mathrm{y}=\mathrm{b} \cdot \mathrm{e}^{-0 / \mathrm{a}}=\mathrm{b}\left[\because \mathrm{e}^{0}=1\right] $$
So slope point of intersection on the curve with `Y` axis is `(0, b)`

Now slope of the given line at `(0, b)` is given by
$$
\begin{aligned}
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