Short answers, pulled from the story.
The concept of zero as a number emerged from the Indian subcontinent during the Vedic period, originating from ritualistic fire altars before becoming the cornerstone of modern arithmetic.
Aryabhata revolutionized trigonometry in 499 CE by defining the sine function as the modern half-chord and creating the first tables of sine and cosine values with four decimal places of accuracy.
Madhava of Sangamagrama founded the Kerala School of astronomy and mathematics in the 14th century, producing the first known power series for sine, cosine, and arc tangent.
Mathematical texts were preserved through a rigorous oral tradition using complex recitation techniques such as the Jata, where every two adjacent words were recited in their original order, then reversed, and then repeated again.
The earliest surviving evidence of the decimal place-value system dates back to the 7th century CE, with copper plates from Gujarat and stone inscriptions in Indonesia and Cambodia bearing dates written in decimal notation.