题目
题型:不详难度:来源:
A.lg(x2+1)≥lg2x | B.x2+1>2x | ||
C.
| D.x2+4≥4x |
答案
B.当x=1时,x2+1=2x,所以B错误.
C.当x=0时,
1 |
x2+1 |
D.由不等式的性质可知x2+4=x2+22≥2×2x=4x,所以D正确.
故选D.
核心考点
举一反三
π |
2 |
A..若
| B..若
| ||||||||||||
C..若x<
| D.若x<
|
A.0.56<log0.56<60.5 | B.0.56<60.5<log0.56 |
C.log0.56<60.5<0.56 | D.log0.56<0.56<60.5 |