专题2.6 函数的图象【七大题型】
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ä 1U2024·hi·åæçèYÑ
𝑓(𝑥) = |2𝑥+ 2| + |3𝑥−3|
(1)[𝑓(𝑥)!"#¹
(2)<:;+𝑓(𝑥) < 6!)é
+ 1-1U2024·êëëì·íåYÑ
𝑓(𝑥) = |2𝑥+ 1| + |𝑥+ 𝑚|UÓL𝑚∈[−1,0]Y
(1)HÔ6!îïðñÚL[𝑚= −
1
2
𝑓(𝑥)!"#¹
(2)<
𝑓(𝑥)!"#aò𝑦= 3AóÝô{!îõ!×?M¡öîõ×𝑚!?
+ 1-2U23-24 vº·º÷·ÂøYH»î!ðñÚL[»W
!"ù
(1)𝑦= 𝑥−2
(2)𝑦= |2𝑥−2|
+ 1-3U2024·úûüý·åæçèYÑ
𝑓(𝑥) = |𝑥+ 1|−2|𝑥−1|.
(1)þ[
𝑓(𝑥)!"#M¡<𝑓(𝑥) ≥1!)é¹
(2)∀𝑥∈(0, + ∞)M𝑓(𝑥) > 𝑎𝑥+ 𝑏M<𝑎+ 𝑏!×?.
2
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ä 2U2024·êëìÿ·åæçèY
𝑓(𝑥) = 𝑥3cos𝑥!ĀG"#oU Y
A
B
C
D
+ 2-1U2024·ìāàĂ·íåY
𝑓(𝑥) = |𝑥2−4|
𝑥
!"#ă
U Y
A
B
C
D
+ 2-2U2024·Ąą·åæçèY
𝑓(𝑥) =
e𝑥−e−𝑥
|1−𝑥2|!"#ăoU Y
A
B
C
D
+ 2-3U2024·úû·åæçèY
𝑓(𝑥) = (𝑥3−2𝑥−1)ln|𝑥|!ă"#tuoU Y
A
B
C
D
3 &'
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ä 3U2024·Ćć·ĈåYÑ
𝑓(𝑥)!ĀG"#V"ĉZMĊ
𝑓(𝑥)!)*+tuoU Y
A𝑓(𝑥) = −
2𝑥2
|𝑥|−1
B𝑓(𝑥) = −
2𝑥2
|𝑥|+1
C𝑓(𝑥) = −
2𝑥
|𝑥|−1
D𝑓(𝑥) = −
2|𝑥|
𝑥2−1
+ 3-1U2024·de·ĈåY
𝑓(𝑥)!"#V"ĉZMĊ𝑓(𝑥)!)*+tuoU Y
A𝑓(𝑥) =
ln|𝑥|
𝑥2+1
B𝑓(𝑥) = e𝑥−e−𝑥
𝑥2
C𝑓(𝑥) = 𝑥2−1
𝑥
D𝑓(𝑥) =
ln|𝑥|
𝑥
+ 3-2U2024·de·ĈåYÑ
𝑦= 𝑓(𝑥)!ĀG"#V"ĉZMĊ𝑓(𝑥)!)*+tuoU Y
A𝑓(𝑥) = e𝑥+1
e𝑥−1
B𝑓(𝑥) =
e𝑥−1
e𝑥+1
C𝑓(𝑥) =
𝑥2
3 𝑥4−1
D𝑓(𝑥) =
𝑥
3 𝑥4−1
+ 3-3U2024·ċČčĎ·våY
𝑦= 𝑓(𝑥)!"#V"①ĉZMĊV"②ĉZ!
"#ĉ¢!
)*+tuoU Y
A𝑦= 𝑓1−1
2 𝑥
B𝑦= −𝑓1−1
2 𝑥
C𝑦= 𝑓(4−2𝑥)
D𝑦= −𝑓(4−2𝑥)
4 ,-./01
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ä 4U2024·Ąą·ĈåYV"ĉZM./𝑃Hôďo 1 !ĐS{𝐴𝐵𝐶𝐷!ôºđ𝐴→𝐵→𝐶→𝐷^.M𝑥XZ
./𝑃 A /Ēĉ!`M𝑦XZ △𝐴𝑃𝐷!îõMĊ
𝑦= 𝑓(𝑥)!ă"ù
U Y
A
B
C
D
+ 4-1U2024·ēąĔĄ·åæçèYV"M/𝑃Hôďo 1 !ĐS{ôº^.M𝑀
𝐶𝐷!L/MR/𝑃
đ𝐴−𝐵−𝐶−𝑀^.M/𝑃!`𝑥a △𝐴𝑃𝑀!îõ𝑦!
𝑦= 𝑓(𝑥)!"#!{ĕă
U Y
A
B
C
D
+ 4-2U2023·÷ćĖėĘę]¨·íåYĚěHV"ĉZ!ĜĝUÓL¶9·ãôG%
ã8ĞğY
ºĠġĜĢMģ±/𝐴ĤĒMđĥĦSħ/𝐵9𝐶9𝐷Ĩĩ /𝐴MĪ80īMģ!OĬĚĭHĮ6
/𝑂¨¸įİĚěĜĢ!`MıĚěĜĢ!Öo𝑡U]¨
īYMģaOĬĚĭÖ!IJijo𝑦U]¨
ĴYM𝑦= 𝑓(𝑡)MĊ𝑓(𝑡)!"#ăoU Y
A
B
C
D
+ 4-3U2024·Ćć·våY"L!ĵªĀGĶo 1Mo 1 !;ķíï{©o 2 q 3 !ãĸ{ĉ
Ĺóı
SĺS(a)(a≥0)
"LĵªĀGĻÐļò yĺ0 © yĺa ĽÖ!ľvĀG!îõMĊ
S(a)!
"#ăo(ĿĿ)
A
B
C
D
5 2"#01
!34
ä 5U2024·úûćŀ·ĈåYÑ
𝑓(𝑥) =
3
𝑥MĊ
𝑦= 𝑓(𝑥−1) +1!"#U Y
AÐ/(1,1)
BÐ/(−1,1)
CÐ/(−1,0)
DÐ/(1,0)
+ 5-1U23-24 vº·ŁłŃĎ·ńŅņŇYV"ĉZ
𝑦= 𝑓(𝑥)!"#M"LňòaòʼnŊ
ŋÙ
Ō:ōŎMĊm»ŏĐ5!
U Y
A
𝑓(𝑥)!6²³o[−4,4)
B
𝑓(𝑥)!?³o[0,5]
CŐ
H6²³L:]½
DÐő£!𝑦∈[0, + ∞)MŒÜœv!ŔË x aĽ¢
+ 5-2U23-24 vº·ēëŕĎ·ÂLY6²H[−5,5]º!É
𝑓(𝑥)H[0,5]º!"#V»"M»WŖ
T:Đ5!
U Y
A𝑓(𝑥)ŗÜv8]½ŘÕÖ
B𝑓(𝑥)Üã8]½ŘÕÖ
C𝑓(𝑥)HÓ6²³ř!×?
5
D𝑓(𝑥)HÓ6²³ř!×Ě?
−5
+ 5-3U23-24 vº·ĆŚśŜ·ÂLYŝI
𝑥1,𝑥2, ⋅⋅⋅,𝑥𝑛L!×
omax{𝑥1,𝑥2, ⋅⋅⋅,𝑥𝑛}M×Ě
o
min{𝑥1,𝑥2, ⋅⋅⋅,𝑥𝑛}MĊÐ
𝑓(𝑥) = min{𝑥+ 1,𝑥2−𝑥+ 1,−𝑥+ 6}!ŖTLĐ5!
U Y
AS`𝑓(𝑥)−1 = 0Üí8&
B𝑓(𝑥)!]½ŘÕÖo −∞, 1
2 q 5
2 , + ∞
C𝑓(𝑥)!×?o
7
2
D𝑓(𝑥)!×Ě?o
3
4
6 2"#567/8
9):;+
ä 6U2023·hi·åæçèYÑ
𝑓(𝑥)!6²³o[−2,4]MÓ"#V"ĉZMĊ𝑥𝑓(𝑥) ≤0!)é
oU Y
A{𝑥|−2 ≤𝑥< −1}
B{𝑥|−1 ≤𝑥≤0}
C{𝑥|1 ≤𝑥≤3}
D{𝑥|0 ≤𝑥≤4}
+ 6-1U2024·ŞćşŠ·íåYÑ6²H R º!È
𝑓(𝑥)H[0, + ∞)º!"#V"ĉZMĊ:;
+𝑥2𝑓(𝑥) > 2𝑓(𝑥)!)éoU Y
A(−2,0) ∪( 2,2)
B(−∞,−2) ∪(2, + ∞)
C(−∞,−2) ∪(−2,0) ∪( 2,2)
D(−2,−2) ∪(0, 2) ∪(2, + ∞)
+ 6-2U2024·úûšŢţ·åæçèYÑ6²H𝑅º!È
𝑓(𝑥)ŤÜ𝑓(𝑥−1) = 𝑓(𝑥+ 1)MR𝑥∈[0,1)
M𝑓(𝑥) = −
1
4𝑥3 +
3
4𝑥MÑ𝑘∈−1
5 ,−1
10 MĊ
𝑔(𝑥) = 𝑓(𝑥)−𝑘𝑥−
1
2H(−1,6)º!7/8
oU Y
A4
B5
C3 x 4
D4 x 5
+ 6-3U2023·pťŦŧŨ·åæçèYÑ
𝑓(𝑥) =
𝑥+ 1
2 ,𝑥∈0, 3
2
2−𝑓𝑥−3
2 ,𝑥∈3
2 , + ∞
MĊ𝑓(𝑥) > |log2𝑥|!
)é
U Y
A 1
2 ,1
B(1,2)
C 1
2 ,2
D 1
2 ,1 ∪(1,2)
7 2"#<=
!>?@A
ä 7U2024·ŞŚŜũŪ·íåYÔ6
𝑓(𝑥) = |𝑥2 + 𝑥|,𝑔(𝑥) = 𝑥+
1
𝑥M𝑀(𝑥)XZ𝑓(𝑥),𝑔(𝑥)L!ūŬM
ŝ𝑀(𝑥) = max{𝑓(𝑥),𝑔(𝑥)}
𝑦= 𝑀(𝑥)!"#a𝑦= 𝑎Ü 3 8:O!Ŏ/MĊI
𝑎!>?@A
+ 7-1U2024·êëëì·våY 𝑓(𝑥) =
e𝑥+ 1,𝑥≤0
1
𝑥,𝑥> 0
M𝑦= 𝑓(𝑓(𝑥)+ 1)−𝑘Üã87/MĊ𝑘!>?
@A
.
+ 7-2U2024·hi·åæçèYÑ
𝑓(𝑥) = |log2(𝑥−1)|,𝑥> 1
|3𝑥−1|,𝑥≤1
MÐ𝑥!S`𝑓(𝑥) = 𝑚Ü 3 8
:ō;!I
&MĊ𝑚!>?@A
+ 7-3U2024·deŭŮ·våYı
𝑓(𝑥) = |log2(𝑥−1)|,1 < 𝑥≤3
(𝑥−4)2,𝑥> 3
M𝑓(𝑥) = 𝑎Üú8I
&𝑥1M
𝑥2M𝑥3M𝑥4Mů𝑥1 < 𝑥2 < 𝑥3 < 𝑥4MĊ
1
4(𝑥3 + 𝑥4)𝑥1 +
1
𝑥2!>?@A
v9]
1U2024·de·åæçèY»W"#LM:tuóo
𝑓(𝑥) = 𝑥3 +
𝑡
𝑥!"#!
U Y
A
B
C
D
2U2024·ČŰűŲ·åæçèY
𝑦= cos𝑥a𝑦= lg|𝑥|!"#!Ŏ/8
U Y
A2
B3
C4
D6
3U2023·ųŴŵŶ·íåYÑ
Ċ
𝑓(𝑥) = 𝑥2,𝑥≥0,
1
𝑥,𝑥< 0, 𝑔(𝑥) = 𝑓(−𝑥)
MĊ
𝑔(𝑥)!"#ă
U Y
A
B
C
D
4U2023·hi·åæçèY
𝑦= 𝑓(𝑥)HÕÖ[−3,3]!ă"#V"MĊ
𝑓(𝑥)!)*+tuoU Y
A𝑓(𝑥) =
2𝑥sin𝑥
𝑥2+1
B𝑓(𝑥) =
2𝑥cos𝑥
𝑥2+1
C𝑓(𝑥) =
3𝑥
𝑥2−1
D𝑓(𝑥) =
4𝑥cos𝑥
𝑥2+1
5U2024·ìā·åæçèYV"Mò𝑙HŷŸ¨¸a;ô △𝐴𝐵𝐶!ĶôpàMĽ𝑙ŹŸHîºźŻ
żSħŽ/𝐴Ġġâ.Uâ.ï~:ž60°YMſƀ!íï{řĵªĀG!îõ𝑆
Ö𝑡!
8
!"#ă
U Y
A
B
C
D
6U2024·řƁƂƃƄ·våYH»Wú8"{LM/ P ±/ O ĒMźŻżSħđÁďo l !"{^.
vÁMO9P ã/ƅò!IJij y a/ P Ɔ!` x !
ÚV"MľƇ/ P ĉƆ!"{
U Y
A
B
C
D
7U2024·pť·åæçèYÑ
𝑓(𝑥)
6²HRºÁÂo 4 !È
Mů𝑓(𝑥) =
𝑥,0 ≤𝑥< 1
−𝑥+ 2,1 ≤𝑥≤2
MĊ
:;+𝑥𝑓(𝑥−1) < 0H(−2,2)º!)éoU Y
A(−2,−1)
B(−2,−1) ∪(0,1)
C(−1,0) ∪(0,1)
D(−1,0) ∪(1,2)
8U2024·úû·åæçèYÑ
𝑦= 𝑓(𝑥−2)!"#Ðò𝑥= 2Mő£!𝑥∈𝑅MŒÜ𝑓(𝑥+ 3) = 𝑓
(𝑥−1)óƈMůR𝑥∈[−2,0]M𝑓(𝑥) = −𝑥MHÕÖ(−2,10)řS`𝑓(𝑥)−log𝑎(𝑥+ 2) = 0Ü 5 8:O!I
&MĊI
𝑎!>?@AoU Y
A(2,2 2)
B(2,2 2]
C(2 2,2 3)
D(2 2,2 3]
Ĉ9Ý
9U2024·ìāàĂ·våY
𝑓(𝑥) = 𝑥3−
𝑚
𝑥(𝑚∈R)!"#tu
U Y
A
B
C
D
10U2024·ìāàĂ·våYÑ𝑎> 0M
𝑓(𝑥) = 𝑥𝑎−𝑎𝑥(𝑥> 0)!"#tu
U Y
A
B
C
D
11U2024·ĄąƉƊ·íåYHîïðñÚ𝑥𝑂𝑦LMV"Ƌ¸!ôďo 2 !ĐS{𝐴𝐵𝐶𝐷đ𝑥ƌƍ.Uʼn
Ǝ.ƍ.YM/𝐷QƏðñƐ/MıƑ/𝐵(𝑥,𝑦)!ƒƓS`
𝑦= 𝑓(𝑥)MĊU Y
AS`𝑓(𝑥) = 2H[−3,9]ºÜí8&
B𝑓(−𝑥) = −𝑓(𝑥)
C𝑓(𝑥)H[6,8]º]½Ɣƕ
Dő£𝑥∈𝑅MŒÜ𝑓(𝑥+ 4) = −
1
𝑓(𝑥)
í9yz
12U2024·º÷ƖĄ·våYı𝑎、𝑏oØ
M𝑎> 1,𝑏< −1MĊ
𝑦= 𝑎𝑥+𝑏!"#Ɨ6:g
#Ŋ.
13U2024·hi·åæçèYÑ
𝑓(𝑥) =
𝑥
𝑥−1,𝑔(𝑥) = e𝑥−1−e−𝑥+1 +1MĊ𝑓(𝑥)a𝑔(𝑥)!"#Ŏ/!Ƙð
ñĽqo
14U2024 í·hi·ņŇYıÈ
𝑓(𝑥)!6²³o[−5,5]R𝑥∈[0,5]M𝑓(𝑥)!"#V"MĊ
:;+𝑓(𝑥) < 0!)é
ú9)ƙ
15U2024·Ąąƚƛ·åæçèYÑ
𝑓(𝑥) = 𝑥−[𝑥],𝑥∈[−1,2)MÓL[x]XZ:ž𝑥!×Ɯ
MäV
[−3.05] = −4,[2.1] = 2.
(1)Ɲ𝑓(𝑥)!)*+ƞóGŅ
!{+;
(2)þHV"ĉZ!îïðñÚL
𝑓(𝑥)!"#;
(3)&'"#ƞ
𝑓(𝑥)!?³.
16U2024·úûüý·åæçèYÑ
𝑓(𝑥) = |2𝑥−3| + |𝑥+ 1|−5
(1)<:;+𝑓(𝑥) ≤6!)é¹
(2)ò𝑦= 𝑘(𝑥+ 1)a𝑓(𝑥)!"#ĉAó!íï{!îõo
15
2 M<I
𝑘!?
17U2023·hi·åæçèYÑ
𝑓(𝑥) = |𝑥+ 3|−|𝑥−2|
(1)[𝑓(𝑥)!"ùM¡ƞ𝑓(𝑥)!?³¹
(2):;+𝑓(𝑥) ≤3𝑎2−4𝑎+ 1ŤóƈM<I
𝑎!>?@A
18U2024·hi·åæçèYÑ
𝑓(𝑥) = |𝑥+ 𝑎| + |𝑥−2|(𝑎∈𝑅)Mů𝑓(𝑥) ≤1Ü)
(1)< a !>?@A¹
(2)R a >×?M𝑔(𝑥) = 3𝑓(𝑥)−2|𝑥−2|−3!"#M¡<𝑔(𝑥)!"#a x ƌAó!ƟƠ"{!îõ
19U23-24 vº·ēëŕĎ·ÂLYÑ
𝑓(𝑥)
6²H𝑅º!É
MR𝑥≥0M𝑓(𝑥) = 𝑥2−2𝑥.
U1Y<
𝑓(𝑥)!)*+M¡[
𝑓(𝑥)!"#¹
U2Y&'"#ƞ
𝑓(𝑥)!]½ƔŘÕÖq?³¹
U3YơƢS`𝑓(𝑥) = 𝑎(𝑎∈𝑅))!8
.