How do I use the binomial theorem to find the constant term?
From the binomial expression, write down the general term. Let this term be the r+1 th term. Now simplify this general term. If this general term is a constant term, then it should not contain the variable x.
Let us write the general term of the above binomial.
simplifying, we get,
Now for this term to be the constant term,
=> 3-r =0
Thus, the fourth term in the expansion is the constant term. By putting r=3 in the general term, we will get the value of the constant term.