Early Astronomy

Ancient Greek astronomy

Ancient Greek astronomy is the astronomy written in the Greek language during classical antiquity.

Trigonometria

La trigonometria (del grec: "la mesura de triangles") és una branca de les matemàtiques que tracta les relacions internes dels triangles.

Greek contributions to the Islamic world

Greece played a crucial role in the transmission of classical knowledge to the Islamic world.

弦函數

弦函數（chord function）是最早的三角函數之一 ，符號通常表示為的弦與半徑的比值，和句話說，就是單位圓上角的終邊端點到始邊端點的距離.