作业帮化简:(2cos^2α-1)/[2tan(π/4-α)sin^2(π/4+α)]
来源：学生作业帮助网 编辑：作业帮 时间：2024/05/04 03:34:26
![化简:(2cos^2α-1)/[2tan(π/4-α)sin^2(π/4+α)]](/uploads/image/z/757122-42-2.jpg?t=%E5%8C%96%E7%AE%80%3A%282cos%5E2%CE%B1-1%29%2F%5B2tan%28%CF%80%2F4-%CE%B1%29sin%5E2%28%CF%80%2F4%2B%CE%B1%29%5D)
化简:(2cos^2α-1)/[2tan(π/4-α)sin^2(π/4+α)]
化简:(2cos^2α-1)/[2tan(π/4-α)sin^2(π/4+α)]
化简:(2cos^2α-1)/[2tan(π/4-α)sin^2(π/4+α)]
(2cos^2a-1)/[2tan(45度-a)*sin^2(45度+a)]
=cos2a/[2tan(45度-a)*cos^2(45度-a)]
=cos2a/[2sin(45度-a)*cos(45度-a)]
=cos2a/sin(90度-2a)
=cos2a/cos2a
=1