Cosine integral
From specialfunctionswiki
The cosine integral is defined by $$\mathrm{Ci}(z) = -\displaystyle\int_z^{\infty} \dfrac{\cos t}{t} dt ; |\mathrm{arg} z|<\pi.$$
- Ci.png
Graph of $\mathrm{arccos}$ on $(0,20)$.
Domain coloring of analytic continuation of $\mathrm{Ci}$.
Videos
Laplace transform of cosine integral