Question

What mathematicians helped to discover alternatives to euclidean geometry in the nineteenth century

Answer 1

Nikolai Lobachevsky and Bernhard Riemann

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Answer 2

Nikolai Lobachevsky and Bernhard Riemann

Explanation:

Nikolai Lobachevsky (A russian mathematician born in 1792) and Bernhard Riemann (A german mathematician born in 1826) are the mathematicians that helped to discover alternatives to euclidean geometry in the nineteenth century.