Question

If $n$ is a positive integer, then the number of terms in the expansion of $(x+a{)}^n$ is

• A. $n$
• B. $n+1$
• C. $2n$
• D. Infinitely many

Answer 1

The correct option is B $n+1$

In binomial expansion the terms goes from $n{C}_0{x}^n$ to $n{C}_n{a}^n$ i.e the base of $C$ goes from $0$ to $n$ and this shows that there must be $(n+1)$ terms.