Binomial TheoremHard
Question
-The coefficient of x′ (0 ≤ r ≤ n - 1) in the expression :
(x + 2)n-1 + (x + 2)n-2. (x + 1) + (x + 2)n-3. (x + 1)2 + ...... + (x + 1)n-1 is -
(x + 2)n-1 + (x + 2)n-2. (x + 1) + (x + 2)n-3. (x + 1)2 + ...... + (x + 1)n-1 is -
Options
A.nCr (2r - 1)
B.nCr (2n-r - 1)
C.nCr (2r + 1)
D.nCr (2n-r + 1)