重难点03 指、对、幂数的大小比较问题【八大题型】
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Å 1Æ2024·ÇÈÉÊ·ËÌÍÎÏÐE𝑎= 30.3H𝑏= 0.33H𝑐= log0.33HÑ𝑎H𝑏H𝑐 %&@Æ Ï
A𝑎> 𝑏> 𝑐
B𝑏> 𝑎> 𝑐
C𝑐> 𝑏> 𝑎
D𝑐> 𝑎> 𝑏
7d 1-1Æ2024·ÒÓÔÕ·ºËÏÐE𝑎= log2
1
3H𝑏= 1.20.2H𝑐= 0.52.1HÑ aHbHc %&@Æ Ï
A𝑎< 𝑐< 𝑏
B𝑐< 𝑎< 𝑏
C𝑐< 𝑏< 𝑎
D𝑎< 𝑏< 𝑐
7d 1-2Æ2024·Ö×ÖÊ·ºËÏÐE𝑎= 40.3,𝑏= (log4𝑎)4,𝑐= log4(log4𝑎)HÑÆ Ï
A𝑎> 𝑏> 𝑐
B𝑎> 𝑐> 𝑏
C𝑏> 𝑐> 𝑎
D𝑐> 𝑎> 𝑏
7d 1-3Æ2024·ØÙÚÛ·ËÌÍÎÏÐE𝑎= log0.20.3H𝑏= ln𝑎H𝑐= 2𝑎HÑ𝑎,𝑏,𝑐 %&ÜÆ Ï
A𝑐> 𝑏> 𝑎
B𝑎> 𝑏> 𝑐
C𝑏> 𝑎> 𝑐
D𝑐> 𝑎> 𝑏
2 '()*#$%&
Å 2Æ23-24 ºÝ·ÞßÈà·áâãäÏÐE𝑎= e0.1H𝑏= 1−2lg2H𝑐= 2−log310HÑ aHbHc %&
@Æ Ï
A𝑏> 𝑐> 𝑎
B𝑎> 𝑏> 𝑐
C𝑎> 𝑐> 𝑏
D𝑏> 𝑎> 𝑐
7d 2-1Æ2024·åæçÓ·ËÌÍÎÏÐE𝑎=
1
e
−1
2,𝑏= log65,𝑐= log56HÑÆ Ï
A𝑎< 𝑏< 𝑐
B𝑐< 𝑏< 𝑎
C𝑏< 𝑐< 𝑎
D𝑎< 𝑐< 𝑏
7d 2-2Æ2024·ØÙèé·°ËÏÐE𝑎= e−1H𝑏= lg𝑎H𝑐= e0HÑÆ Ï
A𝑏< 𝑎< 𝑐
B𝑏< 𝑐< 𝑎
C𝑎< 𝑏< 𝑐
D𝑐< 𝑏< 𝑎
7d 2-3Æ2024·Þßêë·ºËÏÐE𝑎= 0.53.1H𝑏= log0.90.3H𝑐= log1
3
1
2HÑ aHbHc %&Ü
Æ Ï
A𝑐< 𝑏< 𝑎
B𝑐< 𝑎< 𝑏
C𝑏< 𝑎< 𝑐
D𝑎< 𝑐< 𝑏
3 +,)*#$%&
Å 3Æ2024·åæ0ì·ËÌÍÎÏí𝑎= log0.50.6H𝑏= 0.49−0.3H𝑐= 0.6−0.6HÑ𝑎H𝑏H𝑐 %&@
Æ Ï
A𝑐> 𝑏> 𝑎
B𝑏> 𝑎> 𝑐
C𝑏> 𝑐> 𝑎
D𝑐> 𝑎> 𝑏
7d 3-1Æ23-24 °·îÈïð·ñ'ÏÐEò
𝑎,𝑏,𝑐óô2𝑎+𝑎= 2H2𝑏+𝑏=
5H𝑐= log163HÑ
Æ Ï
A𝑐< 𝑎< 𝑏
B𝑎< 𝑏< 𝑐
C𝑎< 𝑐< 𝑏
D𝑏< 𝑐< 𝑎
7d 3-2Æ2024·õö÷Ó·°ËÏø𝑎= log1
3
1
4H𝑏= ( 1
3 )
1
4H𝑐= log3
1
4H𝑑=
1
4ÑÆ Ï
A𝑎> 𝑏> 𝑑> 𝑐B𝑎> 𝑏> 𝑐> 𝑑
C𝑏> 𝑑> 𝑎> 𝑐
D𝑎> 𝑑> 𝑏> 𝑐
7d 3-3Æ2024·Þß^ù·AËÏí 1
3
𝑎
= 2,𝑏= log1
23−log1
29,𝑐=
1
2
−1
3HÑúÆ Ï
A𝑎< 𝑏< 𝑐
B𝑎< 𝑐< 𝑏
C𝑏< 𝑐< 𝑎
D𝑏< 𝑎< 𝑐
4 -.*/-0*#$%&
Å 4Æ2023·ÒÓxt·AËÏø𝑎= 3−1
4H𝑏=
3
2
−1
3H𝑐= log1
2
2
5HÑ𝑎H𝑏H𝑐 %&ÜÆ Ï
A𝑎> 𝑏> 𝑐
B𝑏> 𝑐> 𝑎
C𝑐> 𝑎> 𝑏
D𝑐> 𝑏> 𝑎
7d 4-1Æ2023·Ö×ûüý·ËÌÍÎÏø𝑎=
ln2
2 H𝑏=
ln3
3 H𝑐=
ln5
5 HÑÆ Ï
A𝑎< 𝑏< 𝑐
B𝑐< 𝑏< 𝑎
Cc<a<b
D𝑎< 𝑐< 𝑏
7d 4-2Æ2024·ÒÓxt·°ËÏø𝑎= ln26,𝑏= 4ln2 ⋅ln3,𝑐= (1 + ln3)2HÑ𝑎,𝑏,𝑐 %&@Æ Ï
A𝑐< 𝑎< 𝑏
B𝑎< 𝑏< 𝑐
C𝑐< 𝑏< 𝑎
D𝑏< 𝑎< 𝑐
7d 4-3Æ2024·þÿ·ËÌÍÎÏø𝑎= 20.4,𝑏= 30.25,𝑐= log0.70.5HÑ𝑎,𝑏,𝑐 %&ÜÆ Ï
A𝑎< 𝑏< 𝑐
B𝑏< 𝑎< 𝑐
Cb < 𝑐< a
D𝑐< 𝑎< 𝑏
5 12
*#$%&
Å 5Æ2024·þÿ·ËÌÍÎÏÐE𝑎= ln
7
2H𝑏= ln7 × ln2H𝑐=
ln7
ln2HÑÆ Ï
A𝑏< 𝑐< 𝑎
B𝑏< 𝑎< 𝑐
C𝑎< 𝑏< 𝑐
D𝑎< 𝑐< 𝑏
7d 5-1Æ2024·þÿ·ËÌÍÎÏí𝑎= 5
1
4H𝑏=
5
4H𝑐= log45HÑ aHbHc %&ÜÆ Ï
A𝑎> 𝑏> 𝑐
B𝑎> 𝑐> 𝑏
C𝑏> 𝑎> 𝑐
D𝑏> 𝑐> 𝑎
7d 5-2Æ2024·Þß^ù·AËÏÐE𝑎= log0.20.3,𝑏= log0.30.2,𝑐= log23HÑ𝑎,𝑏,𝑐 %&ÜÆ Ï
A𝑏< 𝑐< 𝑎
B𝑐< 𝑏< 𝑎
C𝑎< 𝑏< 𝑐
D𝑎< 𝑐< 𝑏
7d 5-3Æ2023·ĀÈ·āĂËÌÍÎÏÐEò
𝑎,𝑏,𝑐óô𝑎2 + log2𝑎= 0,2023−𝑏= log2023𝑏,𝑐= log7 6H
ÑÆ Ï
A𝑎< 𝑏< 𝑐
B𝑐< 𝑎< 𝑏
C𝑏< 𝑐< 𝑎
D𝑐< 𝑏< 𝑎
6
345#$%&
Å 6Æ2024·ĀÈ·ËÌÍÎÏÐE𝑎= ln𝜋,𝑏= log3𝜋,𝑐=
𝜋ln2HÑ𝑎,𝑏,𝑐 %&@Æ Ï
A𝑏< 𝑎< 𝑐
B𝑎< 𝑏< 𝑐
C𝑐< 𝑏< 𝑎
Db<c<a
7d 6-1Æ2023·ăæĄ×·°ËÏølog3𝑥= log4𝑦= log5𝑧< −1HÑÆ Ï
A3𝑥< 4𝑦< 5𝑧B4𝑦< 3𝑥< 5𝑧
C4𝑦< 5𝑧< 3𝑥
D5𝑧< 4𝑦< 3𝑥
7d 6-2Æ2024·þÿ·ËÌÍÎÏÐE𝑎=
1
2
𝑎
, 1
2
𝑏
= log𝑎𝑏,𝑎𝑐= log1
2𝑐HÑò
𝑎,𝑏,𝑐 %&ÜÆ Ï
A𝑎< 𝑏< 𝑐
B𝑎< 𝑐< 𝑏
C𝑐< 𝑏< 𝑎
D𝑐< 𝑎< 𝑏
7d 6-3Æ2024·ąÙĆć·ĈAËÏÐE𝑥,𝑦,𝑧ÃÜ%£ 0 ò
Hĉ2𝑥= 3𝑦= log5𝑧HÑ𝑥,𝑦,𝑧%&
Ċċ @Æ Ï
A𝑥> 𝑦> 𝑧
B𝑥> 𝑧> 𝑦
C𝑧> 𝑥> 𝑦
D𝑧> 𝑦> 𝑥
7 6789#$%&
Å 7Æ23-24 ºÝ·ÞßČč·áâãäÏí𝑎、𝑏、𝑐t@Ċ
Hĉ4𝑎= 6𝑏= 9𝑐HÑĎ4ďĐđ @
Æ Ï
A𝑐< 𝑏< 𝑎
B𝑎𝑏+ 𝑏𝑐= 𝑎𝑐
C4𝑏⋅9𝑏= 4𝑎⋅9𝑐
D
1
𝑐=
2
𝑏−
1
𝑎
7d 7-1Æ2024·ăæ·ËÌÍÎÏø𝑎e𝑎= 𝑏ln𝑏(𝑎> 0)HÑÆ Ï
A𝑎< 𝑏
B𝑎= 𝑏
C𝑎> 𝑏
DĒ*ċ
7d 7-2Æ2023·þÿ·ËÌÍÎÏÐE𝑎,𝑏,𝑐ÃÜ
Ä£ 1 Ċò
Hĉln𝑐= 𝑎ln𝑏,ln𝑎= 𝑏ln𝑐HÑ𝑎,𝑏,𝑐
%&@Æ Ï
A𝑐> 𝑎> 𝑏
B𝑏> 𝑐> 𝑎
C𝑎> 𝑏> 𝑐
D𝑎> 𝑐> 𝑏
7d 7-3Æ2024·þÿ·ËÌÍÎÏÐEĊò
𝑎H𝑏H𝑐óôe𝑐+ e−2𝑎= e𝑎+ e−𝑐H𝑏= log23 + log86H
𝑐+ log2𝑐= 2HÑ aHbHc %&Ü( )
A𝑎< 𝑏< 𝑐
B𝑎< 𝑐< 𝑏
C𝑐< 𝑎< 𝑏
D𝑐< 𝑏< 𝑎
8 :;*#$%&
Å 8Æ2024·åææÛ·ËÌÍÎÏø𝑎= 0.311.5,𝑏= log312,𝑐= log26,𝑑=
3 −2
3HÑúÆ Ï
A𝑎> 𝑏> 𝑐
B𝑏> 𝑎> 𝑑
C𝑐> 𝑎> 𝑏
D𝑏> 𝑐> 𝑎
7d 8-1Æ2023·ĀÈē×·ËÌÍÎÏÐE𝑎= log35H𝑏= 2 1
3
1
4H𝑐= 3log72 + log87HÑÆ Ï
A𝑎> 𝑏> 𝑐
B𝑐> 𝑏> 𝑎
C𝑏> 𝑎> 𝑐
D𝑐> 𝑎> 𝑏
7d 8-2Æ2023 Ý·ÛĔ·°āĂáâãäÏÐE𝑎=
19−17,𝑏= 6−3
4,𝑐= log53−
2
9log35HÑÆ Ï
A𝑎< 𝑏< 𝑐
Bb<c<a
C𝑏< 𝑎< 𝑐
Dc<a<b
7d 8-3Æ2024·þÿ·ËÌÍÎÏÐE𝑎= log8.14H𝑏= log3.1eH𝑐= ln2.1,HÑÆ Ï
A𝑎< 𝑐< 𝑏
B𝑎< 𝑏< 𝑐
Cc<a<b
Db<c<a
A/p
1Æ2024·þÿ·ËÌÍÎÏí𝑎= log62H𝑏= log123H𝑐= log405HÑÆ Ï
A𝑎< 𝑏< 𝑐
B𝑏< 𝑎< 𝑐
C𝑐< 𝑎< 𝑏
D𝑎< 𝑐< 𝑏
2Æ2024·ÛĔĕ×·AËÏÐE3𝑚= 4H𝑎= 2𝑚−3H𝑏= 4𝑚−5HÑÆ Ï
A𝑎> 0 > 𝑏
B𝑏> 0 > 𝑎
C𝑎> 𝑏> 0
D𝑏> 𝑎> 0
3Æ2024·Ö×Ėė·AËÏÐE𝑎= 3log83H𝑏= −
1
2log1
316H𝑐= log43HÑ𝑎H𝑏H𝑐 %&ÜÆ Ï
A𝑎> 𝑏> 𝑐
B𝑐> 𝑎> 𝑏
C𝑏> 𝑐> 𝑎
D𝑏> 𝑎> 𝑐
4Æ2023·TĘęĚě·ËÌÍÎÏí𝑎=
3
2
0.7
H𝑏=
2
3
0.7
H𝑐= log3
4(log34)HÑÆ Ï
A𝑐< 𝑏< 𝑎
B𝑎< 𝑏< 𝑐
C𝑐< 𝑎< 𝑏
D𝑎< 𝑐< 𝑏
5Æ2024·îÈĜĝ·ËÌÍÎÏÐE𝑎= e
1
3H𝑏= ln2H𝑐= log32HÑ𝑎,𝑏,𝑐 %&ÜÆ Ï
A𝑎> 𝑐> 𝑏
B𝑎> 𝑏> 𝑐
C𝑏> 𝑐> 𝑎
D𝑐> 𝑏> 𝑎
6Æ2024·åæĞğ·AËÏÐEò
𝑎,𝑏,𝑐óôe2𝑎
2 = e3𝑏
3 = e5𝑐
5 = 2HÑÆ Ï
A𝑎> 𝑏> 𝑐
B𝑎< 𝑏< 𝑐
C𝑏> 𝑎> 𝑐
D𝑐> 𝑎> 𝑏
7Æ2023·ÇÈĠ×·AËÏÐE𝑎= log3π,𝑏=
1
log3π−1,𝑐=
1
2−log3πHÑÆ Ï
A𝑎< 𝑏< 𝑐
B𝑏< 𝑐< 𝑎
C𝑐< 𝑎< 𝑏
D𝑎< 𝑐< 𝑏
8Æ2023·åææÛ·AËÏÐE
𝑓(𝑥) = −2𝑥Hø2𝑎= log2𝑏= 𝑐HÑÆ Ï
A𝑓(𝑏) < 𝑓(𝑐) < 𝑓(𝑎)
B𝑓(𝑎) < 𝑓(𝑏) < 𝑓(𝑐)
C𝑓(𝑎) < 𝑓(𝑐) < 𝑓(𝑏)
D𝑓(𝑐) < 𝑓(𝑏) < 𝑓(𝑎)
°/
9Æ2024·ĀÈìÊ·ËÌÍÎÏĎĊċ @Æ Ï
A2−0.01 > 2−0.001
Blog2 3 > log2π−1
Clog1.85 < log1.75
Dlog33.01 > e−0.01
10Æ2024·Cġ·ËÌÍÎÏø𝑏> 𝑐> 1H0 < 𝑎< 1HÑĎ4ďĊċ @Æ Ï
A𝑏𝑎< 𝑐𝑎
Blog𝑏𝑎> log𝑐𝑎
C𝑐𝑏𝑎< 𝑏𝑐𝑎
D𝑏log𝑐𝑎> 𝑐log𝑏𝑎
11Æ2024·Cġ·AËÏÐE3𝑎= 5𝑏= 15HÑĎ4ďĊċ @Æ Ï
Alg𝑎> lg𝑏
B𝑎+ 𝑏= 𝑎𝑏
C 1
2
𝑎
>
1
2
𝑏
D𝑎+ 𝑏> 4
º/bc
12Æ2023·êĢģù·°ËÏ3−2,2
1
3,log25ºB
'Á%
@
.
13Æ2024·êĢĤ×·ºËÏÐE𝑎= 2−1.1H𝑏= log1
4
1
3H𝑐= log23HѺ%&Ü
ÆĥK&Ħ%
ħĨÏ
14Æ2023·ĩĪīĬ·ËÌÍÎÏÐE𝑎= log 3
3
2
2 H𝑏=
2
2
−3
3 H𝑐= ln
1
eHÑ aHbHc %&Ü
Ò/gĭ
15Æ23-24 A·þÿ·ĮįãäÏÐE𝑥= lnπH𝑦= log52H𝑧= e−1
2
(1)#$ xHy %&
(2)#$ yHz %&
16Æ23-24 º·þÿ·=İÏÆ1Ï#$𝑎𝑎𝑏𝑏?𝑏𝑎𝑎𝑏(𝑎> 0,𝑏> 0) %&
Æ2ÏÐE𝑎> 2H#$log(𝑎−1)𝑎?log𝑎(𝑎+ 1)%&
17Æ23-24 A·ÇÈ·ı{-IJÏ#$𝑎H𝑏H𝑐 %&
(1)ÐE1 < 𝑥< 2H𝑎= (log2𝑥)2H𝑏= log2𝑥2H𝑐= log2(log2𝑥)
(2)ÐE𝑎= log36H𝑏= log510H𝑐= log714
18Æ23-24 AÝ·ąÙăij·áâãäÏÐEĊò
xHyHz óô3𝑥= 4𝑦= 6𝑧
Æ1ÏjĴ
1
𝑧−
1
𝑥=
1
2𝑦
Æ2Ï#$3𝑥,4𝑦,6𝑧 %&
19Æ23-24 AÝ·ąÙą×·áâãäÏÐE
𝑓(𝑥) =
𝑥2
𝑥2+1
(1)ĵĴĝ
𝑓(𝑥)¢®((0, + ∞)Ý pq!
(2)ÐE𝑎= 𝑓(20.5),𝑏= 𝑓(log25),𝑐= 𝑓(0.25)HĶ#$ºB
aHbHc %&Hĵķĝĸ