2023高一上·全国·专题练习
1 . 利用弧度制证明下列关于扇形的公式:其中
是圆的半径,
为圆心角,
是扇形的弧长,
是扇形的面积.
(1)
;
(2)
;
(3)
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4aa0df7f1e45f9de29e802c7f19a4f64.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8a3a2a629b567b9e7b9fc1939d0c8ff8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf231f8f86fb922df4ca0c87f044cec3.png)
(1)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/12c99dda1775e932da70e56868d0dbd8.png)
(2)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/00d79200eeeacf0e1286d8e672259639.png)
(3)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3f3575808fd8f5cfe68372cb7e794ac2.png)
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2 . 已知
为锐角,求证:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c24095e409b025db711f14be783a406c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/17a5d8748d606082935398434f35739d.png)
您最近一年使用:0次