A=[21705.469?599281.681];B=[21740.178?599301.637];C=[21758.724?599322.007];
>>?a=sqrt((B(1)-C(1))^2+(B(2)-C(2))^2);
>>?b=sqrt((A(1)-C(1))^2+(A(2)-C(2))^2);
>>?c=sqrt((A(1)-B(1))^2+(A(2)-B(2))^2);
>>?beta=acos((a^2+c^2-b^2)/(2*a*c))
2.8312這是我用matlab算出來的,原理用的是余弦定理?
答案是:2.8312*57.3=162.2278?°
請樓上說我算錯的人瞧瞧,2.8312是弧度,懂?什麽年代了,妳還筆算?