三角形ABC中a^2+b^2=2c^2求（sin^2A+sin^2B）/Sin^2C

分类: 作业答案 • 2021-12-20 10:06:18

问题描述：

三角形ABC中a^2+b^2=2c^2求（sin^2A+sin^2B）/Sin^2C
0 - 解决时间：2008-5-2 17:12

答

a/c=sinA/sinC,b/c=sinA/sinC
a^2/c^2=sin^2A/Sin^2C,b^2/c^2=sin^2B/Sin^2C .
（sin^2A+sin^2B）/Sin^2C =（a^2+b^2）/c^2=2