Question

已知三条边长分别为a=2√2,b=2,c=√6+√2 ,求角A、B、C.

Answer 1

用余弦定理,cosC = (a^2 + b^2 - c^2) / (2·a·b) cosB = (a^2 + c^2 - b^2) / (2·a·c) cosA = (c^2 + b^2 - a^2) / (2·b·c) 自己算算吧~good luck