關於「Find turning point」標籤，搜尋引擎有相關的訊息討論：

How to Find Turning Point by Completing the Square - Jimmy Mathsjimmymaths.com › find-turning-point-by-completing-the-s...Finding the turning point and the line of symmetry - BBCwww.bbc.co.uk › bitesize › guides › revisionLeaving Cert Maths - Calculus 17 - Turning Points - YouT