想必现在有很多小伙伴对于确定下列各三角函数数值的符号：$\left ( {1} \right )sin{830}^{\circ }$；$\left ( {2} \right )sin\left ( {-\dfrac {35\pi } {17}} \right )$；$\left ( {3} \right )tan{500}^{\circ }$；$\left ( {4} \right )cos\left ( {\dfrac {47\pi } {9}} \right )$.","title_text":"确定下列各三角函数数值的符号：$\left ( {1} \right )sin{830}^{\circ }$；$\left ( {2} \right )sin\left ( {-\dfrac {35\pi } {17}} \right )$；$\left ( {3} \right )tan{500}^{\circ }$；$\left ( {4} \right )cos\left ( {\dfrac {47\pi } {9}} \right )$.方面的知识都比较想要了解，那么今天小好小编就为大家收集了一些关于确定下列各三角函数数值的符号：$\left ( {1} \right )sin{830}^{\circ }$；$\left ( {2} \right )sin\left ( {-\dfrac {35\pi } {17}} \right )$；$\left ( {3} \right )tan{500}^{\circ }$；$\left ( {4} \right )cos\left ( {\dfrac {47\pi } {9}} \right )$.","title_text":"确定下列各三角函数数值的符号：$\left ( {1} \right )sin{830}^{\circ }$；$\left ( {2} \right )sin\left ( {-\dfrac {35\pi } {17}} \right )$；$\left ( {3} \right )tan{500}^{\circ }$；$\left ( {4} \right )cos\left ( {\dfrac {47\pi } {9}} \right )$.方面的知识分享给大家，希望大家会喜欢哦。

龙8国际官网下载（1）$sin83{0}^{circ }=sinleft ( {72{0}^{circ }+11{0}^{circ }} right )$

龙8国际官网下载$=sin11{0}^{circ }$

$because 11{0}^{circ }$是第二象限角，

龙8国际官网下载$therefore sin11{0}^{circ }gt 0$

龙8国际官网下载即$sin83{0}^{circ }gt 0$

综上所述，结论是：$+$；

（2）$sinleft ( {-dfrac {35pi } {17}} right )=sinleft ( {-2pi -dfrac {pi } {17}} right )$

$=-sindfrac {pi } {17}$

$because dfrac {pi } {17}$是第一象限角，

$therefore -sindfrac {pi } {17}lt 0$

即$sinleft ( {-dfrac {35pi } {17}} right )lt 0$

综上所述，结论是：$-$；

（3）$tan50{0}^{circ }=tanleft ( {3{60}^{circ }+14{0}^{circ }} right )$

$=tan14{0}^{circ }$

龙8国际官网下载$because 14{0}^{circ }$是第二象限角，

$therefore tan14{0}^{circ }lt 0$

龙8国际官网下载$therefore tan50{0}^{circ }lt 0$

综上所述，结论是：$-$；

龙8国际官网下载（4）$cosdfrac {47pi } {9}=cosleft ( {5pi +dfrac {2pi } {9}} right )$

$=-cosdfrac {2pi } {9}$

$because dfrac {2pi } {9}$是第一象限角，

$therefore -cosdfrac {2pi } {9}lt 0$

$therefore cosleft ( {dfrac {47pi } {9}} right )lt 0$

龙8国际官网下载综上所述，结论是：$-$.

本文到此结束，希望对大家有所帮助。

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