2013届新课标高中数学(文)第一轮总复习第4章第27讲三角函数的图象与性质(二)_图文
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1 1/2() 2 () 1 1 /3
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25
f x1 f x f x2 | x1
x2 |_____2__________
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2
)f xg x
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3.xaf xsinxg x
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______2________
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| 2sin(a ) |
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2
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2
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2
(x )
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2
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1f xsin(x)
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2
f x
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f xTT 40 46
2
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f xsin x.
6
2f x12 f 1f 2f 120
1028 126
f 1f 2f 3f 102 f 1f 2f 3f 4f 5f 6
2 3.
1 ysinxysin(x) (>0<0 ) y sinxy sin(x) ysinxysin(x)ysin(x) ysinxysinxysin(x)
x
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6
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6
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6
6
2ysin( x 2
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6
26
2""yAsin(x) x XxX0 /2 3 /2 2x yAsin(x) ysinx yAsin(x)