若arcsinx>=1,则x的范围是 A.[sina1,1] B.[ π/2 ,π ] C.[-1/2 ,sina1] D.[0,π/2]注:π此乃 “派”是也~sorry~A选项是A.[sin1,1] C选项是 C.[-1/2 ,sin1]
问题描述:
若arcsinx>=1,则x的范围是
A.[sina1,1] B.[ π/2 ,π ] C.[-1/2 ,sina1] D.[0,π/2]
注:π此乃 “派”是也~
sorry~A选项是A.[sin1,1] C选项是 C.[-1/2 ,sin1]
答
arcsinx∈[-π / 2,π / 2]
-π / 2 ≤ arcsinx ≤ π / 2
1 ≤ arcsinx ≤ π / 2
sin(1) ≤ x ≤ sin(π / 2)
sin(1) ≤ x ≤ 1
答案是A