This chapter is designed to aid students studying AS/A2 Level Mathematics for the New MEI GCE (Maintained under OCR). It ought to comply with the applicable specification for the GCE, available here in pdf format from OCR's website. This books aims at the very least to teach the bare minimum information specified in the official specification, but the reader should note that relying on this textbook alone is ill-advised. All readers are strongly encouraged to make bold additions to these pages, where doing so will improve the book for all/most users. If at any stage you feel that an extra/replacement example would be helpful, please do not hesitate to make the necessary change!