1) Abū al-Wafā Būzhjānī (d. 998) was a Persian Muslim mathematician and astronomer from Khorasan. He established several Trig. identities such as [𝒔𝒊𝒏

1) Abū al-Wafā Būzhjānī (d. 998) was a Persian Muslim mathematician and astronomer from Khorasan. He established several Trig. identities such as [𝒔𝒊𝒏