Kedog

I'm working through Oxford's aa HL Textbook and the solutions at the end of the book are quite often wrong. Even the worked solution book gives false solutions and false steps. Am I the only one who came across this. I really hope that you can help me find another math aa HL textbooks with hard problems and right solutions.

Well my Question is, am I theoretically able to skip 11th grade and go straight to year 12? Means 10->12.

So after reading endless of Ib related threads I came to the conclusion to buy the Haese&Harris Math HL book. But there is this one problem. I can only find a Book from 2008 with the name Haese&Harris. Here a link: https://www.medimops.de/paul-urban-mathematics-for-the-international-students-ib-dipolma-hl-core-taschenbuch-M01876543116.html Is this the one everyone is talking about and is this book good for a 6-7 points reaching student?