Focus Gold (4th Edition) Mathematics IA, IIB, III Set of textbook + answer key (Keirinkan) Used for university entrance exam preparation. Contains examples, checks, and exercises, making it a very easy-to-use reference book for solidifying basic to standard level understanding. [Contents] ・Mathematics IA (Textbook) ・Mathematics IIB (Textbook) ・Mathematics III (Textbook) ・Mathematics IA (Answer Key) ・Mathematics IIB (Answer Key) ・Mathematics III (Answer Key) [Condition] ・Some signs of use due to usage ・Writing, highlighting, and sticky note marks present (see photos) ・No torn pages, no problem for studying ※Please check the photos for the condition. ※Separate sales are also possible, but the set purchase offers a more advantageous price. If you have a desired volume (e.g., only Mathematics III, only the answer key, etc.), please feel free to consult in the comments. ※I plan to go back to my hometown on the 28th, so if you purchase by the 27th, I can ship on the same day. After that, it may take some time to ship. I am selling this as I declutter. Immediate purchase is OK.