  In the pursuit of understanding the large-scale structure of the Universe,
the synergy between complementary cosmological surveys has proven to be a
powerful tool. Using multiple tracers of the large-scale structure can
significantly improve the constraints on cosmological parameters. We explore
the potential of combining the Square Kilometre Array Observatory (SKAO) and
the Dark Energy Spectroscopic Instrument (DESI) spectroscopic surveys to
enhance precision on the growth rate of cosmic structures. We employ a
multitracer Fisher analysis to estimate precision on the growth rate when using
pairs of mock surveys that are based on SKAO and DESI specifications. The pairs
are at both low and high redshifts. For SKA-MID, we use the HI galaxy and the
HI intensity mapping samples. In order to avoid the complexities and
uncertainties at small scales, we confine the analysis to scales where linear
perturbations are reliable. The consequent loss of signal in each individual
survey is mitigated by the gains from the multi-tracer. After marginalising
over cosmological and nuisance parameters, we find a significant improvement in
the precision on the growth rate.
