  We present an analytical solution for the luminosity distance in spatially
flat cosmology with pressureless matter and the cosmological constant. The
complex analytical solution is made of a real part and a negligible imaginary
part. The real part of the luminosity distance allows finding the two
parameters $H_0$ and $\om$. A simple expression for the distance modulus for
SNs of type Ia is reported in the framework of the minimax approximation.
