Let Φ be a Drinfeld Fq​[T]-module of rank 2, over a finite
field L, a finite extension of n degrees of a finite field with q
elements Fq​. Let m be the extension degrees of L over the
field Fq​[T]/P, P is the F-characteristic of
L, and d the degree of the polynomial P. We will discuss about a many
analogies points with elliptic curves. We start by the endomorphism ring of a
Drinfeld Fq​[T]-module of rank 2, EndL​Φ, and we specify
the maximality conditions and non maximality conditions as a
Fq​[T]-order in the ring of division EndL​Φ⊗Fq​[T]​, in the next point we will interested
to the characteristic polynomial of a Drinfeld module of rank 2 and used it to
calculate the number of isogeny classes for such module, at last we will
interested to the Characteristic of Euler-Poincare χΦ​ and we will
calculated the cardinal of this ideals.Comment: 1