OCR FP2 2015 June — Question 9

Exam BoardOCR
ModuleFP2 (Further Pure Mathematics 2)
Year2015
SessionJune
TopicPolar coordinates

9 The equation of a curve in polar coordinates is \(r = 2 \sin 3 \theta\) for \(0 \leqslant \theta \leqslant \frac { 1 } { 3 } \pi\).
  1. Sketch the curve.
  2. Find the area of the region enclosed by this curve.
  3. By expressing \(\sin 3 \theta\) in terms of \(\sin \theta\), show that a cartesian equation for the curve is $$\left( x ^ { 2 } + y ^ { 2 } \right) ^ { 2 } = 6 x ^ { 2 } y - 2 y ^ { 3 } .$$ \section*{END OF QUESTION PAPER}