Past Papers’ Solutions | Cambridge International Examinations (CIE) | AS & A level | Mathematics 9709 | Pure Mathematics 1 (P1-9709/01) | Year 2017 | Feb-Mar | (P1-9709/12) | Q#2
In the expansion of , the coefficient of x is 5. Find the value of the constant a.
We are given expression as;
Expression for the general term in the Binomial expansion of is:
In the given case:
Since we are looking for the terms with i.e. we can equate;
Now we can find the term with; Substituting ;
We are given that the coefficient of x is 5. Therefore;