Who invented a symbol for zeroa.Chandraguptab.Āryabhattac.Varāhamihirad.Brahmagupta

To determine who invented a symbol for zero among the given choices, we can analyze the contributions of each individual:

1. Chandragupta: While an important figure in Indian history, particularly for founding the Maurya Empire, he is not known for contributions to mathematics or the concept of zero.

2. Āryabhata: An ancient Indian mathematician and astronomer, Āryabhata made significant contributions to mathematics, including positional notation, but he did not specifically introduce a symbol for zero.

3. Varāhamihira: A renowned scholar in various fields, including astrology and mathematics. He is known for his work in astronomy, but he did not create a symbol for zero.

4. Brahmagupta: He was an Indian mathematician and astronomer who lived in the 7th century. He explicitly defined zero and its operations in his work "Brahmasphutasiddhanta," thereby formalizing the concept with a symbol.

Final Answer

The correct answer is d. Brahmagupta, who is credited with the formalization and use of a symbol for zero.