余弦定理在双曲平面上的推广

On the Law of Consine in Hypebolie Plane

常高斯曲率曲面上的测地三角形，也存在余弦定理，证明了在双曲平面（k=-1）上的测地三角形，其边长分别为a、b、c，b、c边的夹角为a，它们满足以下余弦定理：在H^2（-1）上：cha=chbchc-shbshccosa。

There is also the consine law on the measured triangle of the common Gauss curvature curved surface.this paper proves the measured triangleon hyperboloid plane (k=-1), whose sides individually are a,b,c, the sides of b,c and their clamping angle, which satisfy the following law of consine.