Question

点P在曲线y=x³-x+上移动,设点P处切线倾斜角为α,则α的取值范围是

A.［0,］                                     B.［0,)∪［,π)

C.［,π)                                    D.(,］

Answer 1

B  ∵y=x³-x+,∴y′=3x²-1≥-1,即在点P处切线的斜率≥-1,

∴α∈［0, )∪［,π).