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问题 解答题
已知角α终边上经过点P(-
3
5
，
4
5
)．
（1）求sinα的值；
（2）求sin(2α-
π
3
)的值．
答案

（1）根据三角函数的定义可知，sinα=

4
5
，cosα=
-3
5

（2）由二倍角公式可得，sin2α=2sinαcosα=-

24
25
，cos2α=2cos2α-1=-
7
25

sin(2α-

π
3
)=sin2αcos
π
3
-sin
π
3
cos2α

=-

24
25
×
1
2
-
3
2
×(-
7
25
)=
7
3
-24
50

单项选择题

An instruction is made up of (41) that specify the function to be performed and operands that represent the data to be operated on. For example, if an instruction is to perform the operation of (42) two numbers, it must know (43) the two numbers are. The processor’s job is to (44) instructions and operands from memory and to perform each operation. Having done that, it signals (45) to send it next instruction.

A．data

B．address

C．register

D．operations
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多项选择题

以下属于政策性银行的是（）

A．国家发展银行

B．中国人民银行

C．中国进出口银行

D．中国农业银行

E．中国农业发展银行
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