The coefficient ofx103 in (1+x+x2+x3+x4)199.(x−1)201 is
8
9
0
11
[(x−1)(x4+x3+x2+x+1)]199(x−1)2 =(x5−1)199(x2−2x+1) Coefficient of x103 is 0 [∴(x5−1)199 will have all powers of x as multiples of 5 only ]
Coefficient of x3 in the expansion of (1+x1−x)2, |x| < 1 is