Question

在三角形ABC中,BC=a,AB=c,tanA/tanB=根号2·c-b/b,求A 要过程,谢谢

Answer 1

(tanA)/(tanB)=sinA/sinB*cosB/cosA=a/b*(a²+c²-b²)/2ac*((b²+c²-a²)/2bc))=(a²+c²-b²)/(b²+c²-a²)=(√2*c-b)/bb(a²+c²-b²)=(√2*c-b)...