## Calculus: Early Transcendentals (2nd Edition)

$\frac{25}{12}$
$$\sum_{k=1}^{\infty} \frac{1}{k}$$ To find the partial sum of the first four terms, we need to find the values when $k=1$, $k=2$, $k=3$, and $k=4$ and add them together. $$\sum_{k=1}^{4} \frac{1}{k} = \frac{1}{1} + \frac{1}{2} + \frac{1}{3} + \frac{1}{4} = \frac{25}{12}$$