Power-law inflation from the rolling tachyon

Modeling the potential by an inverse square law in terms of the tachyon field $\left[V\right(T)=\beta T^{-2}]$ we find an exact solution for a spatially flat isotropic universe. We show that for $\beta >2\mathrm{}\sqrt{3}/3\mathrm{}$ the model undergoes power-law inflation. A way to construct other exact solutions is specified and exemplified.