Past Papers’ Solutions | Cambridge International Examinations (CIE) | AS & A level | Mathematics 9709 | Pure Mathematics 1 (P1-9709/01) | Year 2019 | May-Jun | (P1-9709/11) | Q#3
A sector of a circle of radius cm has an area of cm2. Express the perimeter of the sector in terms of and .
We are given that for the circular sector;
We are required to find expression for perimeter of the circular sector.
Expression for perimeter of a circular sector with radius and angle rad is;
Therefore, for the given circular sector;
Hence, we need arc length of circular sector.
Expression for length of a circular arc with radius and angle rad is;
We are not given angle rad. We need to find angle rad.
Expression for area of a circular sector with radius and angle rad is;
Therefore, for the given case;