一道简单的定积分题目 求解 谢谢

2025-05-10 20:28:42
推荐回答(2个)
回答1:

换元x=2sinu,
=∫(0到π/6)4sin²u*2cosud2sinu
=∫4sin²2udu
=2∫(1-cos4u)du
=2u-sin4u/2
=π/3-√3/4

回答2:

令x=2sinθ,