The coefficient of x4 in the expansion of log (1 + 3x + 2x2) is
163
- 163
174
- 174
If m = C2n, then C2m is equal to
n + C41
3 × C4n
3 × C4n + 1
None of these
The largest term in the expansion of (3 + 2x)50 where x = 15, is
7th
5th
8th
49th
A.
3 + 2x50 = 3501 + 23x50Here, Tr + 1 = 3050 Cr50 2x3rand Tr = 3050 Cr - 150 2x3r - 1But x = 15∴ Tr + 1Tr ≥ 1⇒ Cr50Cr - 150 . 23 . 15 ≥ 1⇒ 102 - 2r ≥ 15r⇒ r ≤ 6Hence, the largest term is 7th.
The coefficient of x4 in (1 + x + x3 + x4)10 is
210
100
310
110
The coefficient of x4 in the expansion of 1 - 3x21 - 2x is equal to
1
2
3
4
If 1 + xn = C0 + C1x + C2x2 + .... + Cnxn ,then C0 + 2C1 + 3C2 + ..... + n + 1Cn is equal to
2n + n 2n - 1
2n + n 2n
2n + n + 12n
2n - 1 + n - 12n
x < 1,the coefficient of x3 in the expansion of log 1 + x + x2 in ascendingnpowers of x,is
23
43
- 23
- 43
The least value of the natural number n satisfying C(n, 5) + C(n, 6) > C(n + 1, 5)
10
11
12
13
The sum of the coefficients in the expansion of (1 + x + x2)n is
2n
3n
In the expansion of (1 + x)n the coefficients of pth and (p + 1) th terms are respectively p and q, then p + q is equal to
n
n + 1
n + 2
n + 3