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3
2
*
Ví dꢊ 2. GTLN – GTNN c
ꢌ
a hàm s
ꢀ
f (x) = sin x −sin x −5sin x + 2 lꢗn lưꢘt là
(C)
5;3
(A) 5;
−3
(B) 5;3
−
(D)
−5;−3
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*
Ví dꢊ 3.
V
ꢆ
i giá tr
ꢃ
nào c
ꢌ
a m thì phương trình x − 2 + 4 − x = 2m có nghiꢊm
(C) − 2 ≤ m ≤ 2
(A) 2 ≤ m ≤ 2
2
2
< m <1
(B)
≤ m ≤1
(D)
2
2
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2
x − m + m
*
Ví dꢊ 4. Tìm m ñꢉ giá tr
ꢃ
nh
ꢋ
nhꢎt cꢌ
a hàm s
ꢀ
f (x) =
trên
ñ
o
ꢑn [0;1] b
ꢒng -2
x +1
ðiꢇn vào chꢈ trꢆng
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3
−π 2π
;
3 3
*
Ví dꢊ 5. Tìm m ñꢉ phương trình cos
ðiꢇn vào chꢈ trꢆng
x
+
cos2
x
−
1
−
m
=
0
có nghi
ꢊ
m x∈
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1
0