| Zu Gengzhi | |
| T: | 祖暅之 |
| S: | 祖暅之 |
| P: | Zǔ Gèngzhī |
| W: | Tsu Keng-chih |
| Also Known As: | Jingshuo |
| T2: | 景爍 |
| S2: | 景烁 |
| P2: | Jǐngshuò |
Zu Geng or Zu Gengzhi (; ca. 480 – ca. 525) was a Chinese mathematician, politician, and writer. His courtesy name was Jingshuo . He was the son of the famous mathematician Zu Chongzhi.[1] He is known principally for deriving and proving the formula for the volume of a sphere. He additionally measured the angular distance between Polaris and the celestial north pole, which was greater 1600 years ago than it is today.