There are various types of fractional derivatives in literature. One of the most natural and well-behaved
fractional derivatives is recently introduced by the authors Khalil et al. [34], namely the conformable fractional derivative. In this paper, some more results about conformable fractional Laplace transform introduced by Abdeljawad [43] are investigated. The invariant subspace method is developed to get the exact
solutions of various conformable time fractional differential equations. Finally, this theory is extended for
the coupled system of conformable fractional differential equations, as well.