mathematica怎么求解方程组

题目

mathematica怎么求解方程组
Reduce[{s1^2 == (x +
r Sin[[Alpha]] Sin[[Beta]])^2 + (r Sin[[Alpha]]
Cos[[Beta]] + d/2)^2 + (h - r Cos[[Alpha]])^2,
s2^2 == (x + r Sin[[Alpha]] Sin[[Beta]] -
l)^2 + (r Sin[[Alpha]] Cos[[Beta]] - d/2)^2 + (h -
r Cos[[Alpha]])^2,0 < [Alpha] < Pi/2,
0 < [Beta] < Pi/2},{[Alpha],[Beta]}]
用 mathematica 始终在运行啊

答案