Finite-dimensional Hopf Algebra A (q, A, N-, M) Of Weak Projection

In [3] D. E. Radford described completely the structure of finite dimen-sional simpie pointed Hop f algebras A(q, a) n) m) and in [i] Peter Schauenburgintroduced weak projection Of bia1gebras. In this thesis, we present a necessary andsuffici.nt condition for A (q, a, n, m) having nontrivial weak projection. Our mainresults are formulated in theorem 2.l, theorem 3.6, theorem 3.7.