# Past Papers’ Solutions | Edexcel | AS & A level | Mathematics | Core Mathematics 1 (C1-6663/01) | Year 2012 | January | Q#2

Question

a.   Simplify

b.   Simplify

giving your answer in the form  , where b and c are integers.

Solution

a.

We are given;

Since ;

Since ;

b.

As demonstrated in (a) we can write the numerator as;

If we need a rational number in the denominator of a fraction, we need to follow procedure of  “denominator rationalization” as given below.

ü If the denominator is of the form  then multiply both numerator and denominator by

ü If the denominator is of the form  then multiply both numerator and denominator by  .

ü If the denominator is of the form  then multiply both numerator and denominator by  .

We have algebraic formula;