Binomial Theorem And Its Simple Applications Question 158
Question: If the sum of the coefficients in the expansion of $ {{(x-2y+3z)}^{n}} $ is 128 then the greatest coefficient in the expansion of $ {{(1+x)}^{n}} $ is
Options:
A) 35
B) 20
C) 10
D) None of these
Show Answer
Answer:
Correct Answer: A
Solution:
- Sum of the coefficient in the expansion $ {{(x-2y+3z)}^{n}} $ is $ {{(1-2+3)}^{2}}=2^{n} $ \ $ 2^{n}=128\Rightarrow n=7 $
Therefore, greatest coefficient in the expansion of $ {{(1+x)}^{7}} $ is $ ^{7}C_3 $ or $ ^{7}C_4 $ because both are equal to 35.
BETA
