[Pramāṇa](https://indike.org/pramana/) › [Studies](https://indike.org/pramana/ins) › [Science, technology and education](https://indike.org/pramana/ins.science) › [Indian Mathematics](https://indike.org/pramana/ins.science.kaye-1915) › c7.42 # Indian Mathematics c7.42 Indian Mathematics c7.42 - **Language:** English ### [c7.42](https://indike.org/pramana/ins.science.kaye-1915.c7.42) 17. Brahmagupta gives a fairly complete set of rules dealing with the cyclic quadrilateral and either he or the mathematician from whom he obtained his material had a definite end in view—the construction of a cyclic quadrilateral with rational elements.—The commentators did not fully appreciate the theorems, some of which are given in the works of Mahāvīra and Śrīdhara; and by the time of Bhāskara they had ceased to be understood. Bhāskara indeed condemns them outright as unsound. "How can a person" he says "neither specifying one of the perpendiculars, nor either of the diagonals, ask the rest? Such a questioner is a blundering devil and still more so is he who answers the question." - [Previous: c7.41](https://indike.org/pramana/ins.science.kaye-1915.c7.41) - [Next: c7.43](https://indike.org/pramana/ins.science.kaye-1915.c7.43) - [Up: c7](https://indike.org/pramana/ins.science.kaye-1915.c7) --- Source: [https://indike.org/pramana/ins.science.kaye-1915.c7.42](https://indike.org/pramana/ins.science.kaye-1915.c7.42) · Pramāṇa