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