  In inflationary models with minimal amount of gravity waves, the primordial
power spectrum of density fluctuations, $A_S^2(k)$, together with the basic
cosmological parameters, completely specify the predictions for the cosmic
microwave background (CMB) anisotropy and large scale structure. Here we show
how we can strongly constrain both $A_S^2(k)$ and the cosmological parameters
by combining the data from the Microwave Anisotropy Probe (MAP) and the galaxy
redshift survey from the Sloan Digital Sky Survey (SDSS). We allow $A_S^2(k)$
to be a free function, and thus probe features in the primordial power spectrum
on all scales. MAP and SDSS have scale-dependent measurement errors that
decrease in opposite directions on astrophysically interesting scales; they
complement each other and allow the measurement of the primordial power
spectrum independent of inflationary models, giving us valuable information on
physics in the early Universe, and providing clues to the correct inflationary
model.
