Example 3.8. Show
that the function
is
differentiable for all
and find its derivative.
Explore Solution 3.8.
Enter the function f[z] and determine if the Cauchy-Riemann equations hold.
![[Graphics:../Images/CauchyRiemannMod_gr_200.gif]](../Images/CauchyRiemannMod_gr_200.gif)
The Cauchy-Riemann equations hold everywhere, so
that
is analytic for all values of z.
![[Graphics:../Images/CauchyRiemannMod_gr_203.gif]](../Images/CauchyRiemannMod_gr_203.gif)
Remark. We can
write this function as
, and
investigate
.
![[Graphics:../Images/CauchyRiemannMod_gr_207.gif]](../Images/CauchyRiemannMod_gr_207.gif)
We have shown that
is differentiable and hence analytic for all z.
Remark.
is
an entire function.