Question

Consider the expression (a + b)n. According to the Binomial Theorem, the kth term in the expanded form of this expression (where k≤ n) is A) C(n, k)*xkyn-k B) C(n, k-1)*xkyn-k C) C(n-1, k)*xkyn-k D) C(n-1, k-1)*xkyn-k

Answer 1

the correct answer is

C.

Answer 2

The Given expression is

`(a+b)^n`

There are (n+1) terms in above expression.

To find the k-th term in the expression , we will evaluate (k+1)-th term.

`T_(k+1)=_(k)^(n)\textrm{C} * a^(k) * b^(n-k)`

⇒If the expression is of the form,

`(x+y)^n`

Then k-th term is given by

`T_(k+1)=_(k)^(n)\textrm{C} * x^(k) * y^(n-k)`

Option A