# 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

1

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6

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4

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1 1/2() 2 () 1 1 /3

/3 2/3 2/3 ysinx ysin(x/2/3)1 ___________(___________________________ _____________________________)_________ ( )

2 yAsin(x )(A>0>0<<0)

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25
f x1 f x f x2 | x1
x2 |_____2__________
2.f xsin(x )g xcos(x
2
)f xg x
_2___________2_________ _____

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cosxMN MN
______2________
MN | sinacosa |
| 2sin(a ) |
4 MN 2.

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2
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2
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f x
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6
f xsin x.
6

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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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26

2""yAsin(x) x XxX0 /2 3 /2 2x yAsin(x) ysinx yAsin(x)