RAS question
Brahmagupta (598-668 CE) was a mathematician who:
Correct answer: (B) Gave rules for arithmetic operations with zero and negative numbers.
Brahmagupta gave rules for arithmetic operations involving zero, negative numbers and positive numbers.
Explanation
Brahmagupta is linked with negative numbers and the rules for their basic operations. Encyclopaedia Britannica gives the point more specifically: among his major mathematical accomplishments, he defined zero as the result of subtracting a number from itself and gave rules for arithmetical operations among negative numbers, described as "debts", and positive numbers, described as "property". This is why option B is the right choice. The question is not asking merely whether he was an astronomer; it asks what mathematical contribution is associated with him. The option about rules for arithmetic with zero and negative numbers matches Brahmagupta's established mathematical contribution.
Why the other options are wrong
- (A) Inventing the computer is not connected with Encyclopaedia Britannica's account of Brahmagupta's mathematical work.
- (C) DNA is outside the mathematical and astronomical context of Brahmagupta's work, with no connection to its discovery.
- (D) Britannica says Brahmagupta devoted chapters of Brahma-sphuta-siddhanta to mathematics, so describing him as someone who only studied astronomy misses the relevant mathematical contribution.
Concept
This tests ancient Indian contributions to mathematics, especially the historical treatment of zero and negative numbers. It recurs in RAS because science and knowledge traditions in ancient India are a standard part of cultural-history preparation.