Joseph-Louis LagrangeChio̍h-sè-hù Lúi La̍k-gông-ji̍t (Hàn-jī: 石世富．磊．落昂日,Hoat-gí: Joseph-Louis Lagrange;1736 nî 1 goe̍h 25 ji̍t – 1813 nî 4 goe̍h 10 ji̍t), pún-miâGiuseppe Lodovico Lagrangia ia̍h-sīGiuseppe Ludovico De la Grange Tournier, sī chi̍t ūiHoat-kok chekÌ-tāi-lī èkhé-bông sî-tāi êsò͘-ha̍k-ka kiamthian-bûn-ha̍k-ka. I bat tī hō͘Phó͘-ló͘-se kok-ôngFriedrich 2-sè chhiáⁿ, Friedrich kā i o-ló kóng i sī "Au-chiu siōng úi-tāi ê sò͘-ha̍k-ka".
Lagrange ê lāu-pē hi-bāng i khì chò lu̍t-su, tān-sī i chū 17 hòe o̍h tio̍hbî-chek-hun khai-sí, tō tùisò͘-ha̍k sán-seng hèng-chhù, chū-án-ne khai-sí gián-kiù sò͘-ha̍k. 1755 nî, i 19 hòe, siá ê lūn-bûn siū-tio̍h sò͘-ha̍k-kaÔ͘-í-la ê tiōng-sī, lâng tō thê-poa̍t--i hō͘ i chòTorino kàu-siū.
Lagrange chá-kî ê gián-kiù hèng-chhù sī kāpiàn-hun-hoat kahtōng-le̍k-ha̍k kiat-ha̍p, hoat-tián chhuthun-sek le̍k-ha̍k, kái-koatgoe̍h-niûthian-pêng-tōng ê būn-tê,bo̍k-chheⁿ sì ê ūi-chheⁿ ūn-tōng, chi̍t-khòa khang-khòe mā tiāⁿ-tiāⁿ hō͘--ì tio̍h-sióng.
1767 nî 9 goe̍h, Lagrange kah in pió-mōe Vittoria Conti kiat-hun.
