Синус положителен в 1 и 2 четвертях, косинус - в 1 и 4, тангенс и котангенс - в 1 и 3.
![image](https://tex.z-dn.net/?f=cos40%3E0%0A%5C%5C%5C%0Asin70%3E0%0A%5C%5C%5C%0Acos113%3C0%0A%5C%5C%5C%0Asin240%3C0%0A%5C%5C%5C%0Acos290%3E0%0A%5C%5C%5C%0Atg98%3C0%0A%5C%5C%5C%0Actg200%3E0%0A%5C%5C%5C%0Asin%28-140%29%3C0)
0
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sin70>0
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cos113<0
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sin240<0
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cos290>0
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tg98<0
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ctg200>0
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sin(-140)<0" alt="cos40>0
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sin70>0
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cos113<0
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sin240<0
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cos290>0
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tg98<0
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ctg200>0
\\\
sin(-140)<0" align="absmiddle" class="latex-formula">
![image](https://tex.z-dn.net/?f=cos%28-300%29%3E0%0A%5C%5C%5C%0Atg%28-120%29%3E0%0A%5C%5C%5C%0Asin+%5Cfrac%7B%5Cpi%7D%7B9%7D+%3E0%0A%5C%5C%5C%0Acos+%5Cfrac%7B13%5Cpi%7D%7B15%7D+%3C0%0A%5C%5C%5C%0Acos+%5Cfrac%7B5%5Cpi%7D%7B3%7D+%3E0%0A%5C%5C%5C%0Atg+%5Cfrac%7B5%5Cpi%7D%7B11%7D%3E0%0A%5C%5C%5C%0Asin+%5Cfrac%7B13%5Cpi%7D%7B5%7D+%3E0%0A%5C%5C%0Acos%28-+%5Cfrac%7B2%5Cpi%7D%7B3%7D%29%3C0++)
0
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tg(-120)>0
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sin \frac{\pi}{9} >0
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cos \frac{13\pi}{15} <0
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cos \frac{5\pi}{3} >0
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tg \frac{5\pi}{11}>0
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sin \frac{13\pi}{5} >0
\\
cos(- \frac{2\pi}{3})<0 " alt="cos(-300)>0
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tg(-120)>0
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sin \frac{\pi}{9} >0
\\\
cos \frac{13\pi}{15} <0
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cos \frac{5\pi}{3} >0
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tg \frac{5\pi}{11}>0
\\\
sin \frac{13\pi}{5} >0
\\
cos(- \frac{2\pi}{3})<0 " align="absmiddle" class="latex-formula">