Question

logx4＜2 ， logx2＞-1， logx2＜1/3

Answer 1

1) logx4＜2 =logx x²,
若x>1， 则4<x² ,=> x>2;
若 0<x<1，则4>x², => 0<x<1
=> x取值范围为(0,1)∪(2,+∞)

2) logx2＞-1=logx x^(-1)=logx (1/x)
x>1时，则2>1/x, => x>1/2, =>x>1;
0<x<1时，则2<1/x, => x<1/2, =>0<x<1/2,
=> x取值范围为(0,1/2)∪(1,+∞)

3)logx2＜1/3=logx x^(1/3)
x>1时，则 2<x^1/3, => x>2³=8;
0<x<1时，则2>x^1/3, => x<8, => 0<x<1;
=> x取值范围为(0,1)∪(8,+∞)

追问

log3x＜0, logx3＞1, log1/3x＞-1 ,log1/3x＞3, log1/2x＜2 ,log3x＞3, log3x＜-2, log2x＜1/2, log2x＞1

追答

log3x＜0, => 01 0 x>1/4
log3x＞3, => x>27
log3x＜-2, =>0 0 x>2
过程跟之前的都一样，记得要自己理解哦，希望可以帮到你的学习o(∩_∩)o