问题 选择题 若角α,β满足-π2<α<β<π2,则α-β的取值范围是( )A.(-π,π)B.(-π,0)C.(-3π2,π2)D.(0,π) 答案 ∵-π2<α<β<π2∴-π2<α<π2,-π2<β<π2∴-π2<-β<π2,α-β<0∴-π<α-β<0故选B.