JEE Main & Advanced
Mathematics
Binomial Theorem and Mathematical Induction
Question Bank
Multinomial theorem, Terms free from radical sign in the expansion(a1/p+b1/q), Problems regarding to three four consecutive terms or coefficients
question_answer
If number of terms in the expansion of \[{{(x-2y+3z)}^{n}}\]are 45, then n=
A)7
B)8
C)9
D)None of these
Correct Answer:
B
Solution :
\[\frac{(n+1)(n+2)}{2}=45\] or \[{{n}^{2}}+3n-88=0\Rightarrow n=8\]..