Recent web services like Google Image Search allow you to upload a query image and find similar Internet photos. This technique is called an image search. In this lecture, I will explain how speed, accuracy, and memory consumption are related to image retrieval, using only the mathematics covered in high school. With this lecture, students will experience that the mathematics taught in high school plays an essential role in describing real-world systems.

NOTE:
- No subtitles. This lecture was conducted only in Japanese.