From Maths Genie, as well as all the excellent GCSE resources, we also have A Level worked examples. There are two AS Sample papers with worked solutions, Pure Mathematics and Statistics and Mechanics; also available are videos and examination questions by topic for both AS and A Level.
Looking at some A Level texts From Hodder, we see My Revision Notes for Pure Mathematics (MEI). Noting the link (on the left) to Answers and Full Worked Solutions, I was curious to see this document. Access to this resource requires registration (free) which I would highly recommend as this free resource is simply excellent. In 146 pages, the questions and fully worked solutions for each section are provided, the categories are ‘Target your revision’, ‘Exam-style’ and ‘Review’ questions. Whilst the document refers to the book, it is complete in itself. I do have and like this book, it is clear, attractively presented and written by very experienced authors. The companion Applied book, similarly has fully worked solutions.
Note the five pages to scroll through to see the various texts; on page 2 you will find the AS Revision notes; again a pdf of full worked answers is available and also a complete set of Test yourself questions for each chapter in the book.
The correct answer with reasoning is provided and also explanations as to why the other responses are incorrect.
Thank you to Hodder for providing such an excellent and useful resource.