a-B a (C + ) p(B+1) 2 a (a + 1) a +2) B (B+ ) (B+2) 3 + 1.Y 1-2-y-(Y+1) 1-2.3-y (Yy +1)-(y +2) 4. If = +An An*+ Bn-2 Ck-3 +an-+ bn* + cn-3+ 4. If 2 +1 T where k is a positive integer, show that the series 2 u, is convergent if A - a - 1 >0 and divergent if A - a - 1 s0.