Binomial Theorem

What is the number of terms in the expansion of $(x + y)^{n}$?...

What is the general term ($r+1$-th term) in the expansion of $(x + y)^{n}$?...

What is the sum of binomial coefficients ${}^{n}C{0} + {}^{n}C{1} + {}^{n}C{2} + \dots + {...

If $n$ is even, the middle term in the expansion of $(x + y)^{n}$ is:...

If $n$ is odd, the middle terms in the expansion of $(x + y)^{n}$ are:...