2
$\begingroup$

Let $f:\mathbb{C}\to\mathbb{C}$ given for $f(z)=\int_0^z \frac{1-e^t}{t} dt-\ln z$ and put $g(x,y)=\text{Re}(f(z))$. While using the computer, how to determine the curve $g(x,y)=0$?

Thanks for the help.

  • 0
    @Dirk: Ok, i will accept your suggestion. I tried to use maple, but had no success. Thanks2011-11-21

1 Answers 1

3

Using Mathematica:

ContourPlot[With[{z = x + I y},                   Re[EulerGamma - ExpIntegralEi[z]]] == 0,              {x, -20, 20}, {y, -20, 20}] 

exponential integral contour

  • 0
    Why not try it out? I've given you the relationship between incomplete gamma and the exponential integral.2011-11-23