(本小題滿分10分)
解不等式:

解:分別求

的零點,即

由

把數(shù)軸

分成三部分:

當

時,

原不等式即

解得

當

時,原不等式即

因為

恒成立,所以

時原

不等式成立;
當

時,原不等式即

,
解得

綜上,原不等式的解集是

練習冊系列答案
相關習題
科目:高中數(shù)學
來源:不詳
題型:單選題
某公司租地建倉庫,每月土地占用費y
1與倉庫到車站的距離成反比,而每月庫存貨物的運費y
2與倉庫到車站的距離成正比,如果在距離車站10 km處建倉庫,這兩項費用y
1和y
2分別為2萬元和8萬元,那么,要使這兩項費用之和最小,倉庫應建在離車站( �。�
查看答案和解析>>
科目:高中數(shù)學
來源:不詳
題型:解答題
【選修4—5:不等式選講】 設函數(shù)

>1),且

的最小值為

,若

,求

的取值范圍。
查看答案和解析>>
科目:高中數(shù)學
來源:不詳
題型:單選題
已知平面區(qū)域

,

(

是常數(shù)),

,記

為事件

,則使

的常數(shù)

有
查看答案和解析>>
科目:高中數(shù)學
來源:不詳
題型:單選題
當
x>1時,不等式
x+

≥
a恒成立,則實數(shù)
a的取值范圍是( )
A.(-∞,2] | B.[2,+∞) | C.(-∞,3] | D.[3,+∞) |
查看答案和解析>>
科目:高中數(shù)學
來源:不詳
題型:單選題
若a>0,b>0,a+b=2,則下列不等式對一切滿足條件的a,b恒成立的是( )
①ab≤1; ②

+

≤

; ③a
2+b
2≥2; ④

≥2
查看答案和解析>>
科目:高中數(shù)學
來源:不詳
題型:單選題
若實數(shù)
a,
b滿足
a+
b=2,則3
a+3
b的最小值是( )
A.18 | B.6 | C.2 | D.3 |
查看答案和解析>>
科目:高中數(shù)學
來源:不詳
題型:單選題
若

,且

,則下列不等式一定成立的是 ( )
查看答案和解析>>