I have a problem with getting the exact value of this integral : $\int_{x}^{+\infty}\frac{e^{-t}}{t}dt$
Any help would be much appreciated.
I have a problem with getting the exact value of this integral : $\int_{x}^{+\infty}\frac{e^{-t}}{t}dt$
Any help would be much appreciated.
Did you try WolframAlpha?
integrate e^(-t)/t, t=x..infinity
yields $\log (x)+\Gamma (0,x)$ for $x>0$. When a result is specified in terms of a special function like this, it's probably not exactly computable. Nonetheless, you can generate numerical approximations easily enough.
log(x) + gamma(0,x) at x=3
or look at a plot
plot log(x) + gamma(0,x)