已知tanα= 12 ，求： 1+2sin(π−α)cos(−2π−α)sin2(−&#_刷题宝

题干

已知tanα=

1

2

，求： π−α−π−α−α−

1
+
2
s
i
n
(
)
c
o
s
(
2
)
s
i
n
2
(
)
s
i
n
2
(

π

5

2

−α) 的值．

上一题下一题 0.0难度选择题更新时间:2018-04-16 11:12:26

答案(点此获取答案解析）

解：

1 + 2 s i n (π - α) c o s

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