三角函数值的计算
1 tga=0.8375
2 tga=0.4188
3 tga=0.2094
4 tga=0.1047
5 tga=1.650
6 tga=0.8250
7 tga=0.4125
8 tga=2.675
9 tga=1.338
10 tga=0.6688
帮我求一下a的角度啊 我不懂啊