A question concerning the cosine rule, every secondary school students uses it. Never I heard teachers explain who discovers it.
My question:
Who was the first to discover the cosine rule formula? $$a^2=b^2+c^2-2bc\cos(A)$$
2026-04-13 01:37:22.1776044242
Who was the first to discover the cosine rule formula?
67 Views Asked by Bumbble Comm https://math.techqa.club/user/bumbble-comm/detail AtRelated Questions in TRIGONOMETRY
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