Sharaf al-Dīn al-Muẓaffar ibn Muḥammad ibn al-Muẓaffar al-Ṭūsī;
(Persian: شرفالدین مظفر بن محمد بن مظفر توسی; c. 1135 – c. 1213) was an Iranian mathematician and astronomer of the Islamic Golden Age (during the Middle Ages).
Tusi was probably born in Tus, Iran. Little is known about his life, except what is found in the biographies of other scientists.
Around 1165, he moved to Damascus and taught mathematics there. He then lived in Aleppo for three years, before moving to Mosul, where he met his most famous disciple Kamal al-Din ibn Yunus (1156-1242). This Kamal al-Din would later become the teacher of another famous mathematician from Tus, Nasir al-Din al-Tusi.
According to Ibn Abi Usaibi’a, Sharaf al-Din was “outstanding in geometry and the mathematical sciences, having no equal in his time”.