<span>Если в 1 цехе х человек, во 2 цехе 0,36*х человек, в третьем (2/3)*0,36х человек.
х+0,36х+2*0,36*х/3=480
1,6х=480
х=300 (1 цех)
300*0,36=108 (2 цех)
108*2/3=72 (3 цех)</span><span>Комментарии </span><span>Отметить нарушение! </span><span>Спасибо (9)</span>Оценить<span>
</span>
![\displaystyle ctg(arccos(-1/3)-\pi)=ctg(-(\pi-arccos(-1/3))=-ctg(\pi -arccos(-1/3))=\\\\=-(-ctg(arccos(-1/3))=ctg(arccos(-1/3))](https://tex.z-dn.net/?f=%5Cdisplaystyle+ctg%28arccos%28-1%2F3%29-%5Cpi%29%3Dctg%28-%28%5Cpi-arccos%28-1%2F3%29%29%3D-ctg%28%5Cpi+-arccos%28-1%2F3%29%29%3D%5C%5C%5C%5C%3D-%28-ctg%28arccos%28-1%2F3%29%29%3Dctg%28arccos%28-1%2F3%29%29)
Далее воспользуемся формулой
![\displaystyle ctg^2x+1=\frac{1}{sin^2x}\\\\ctg^2x=\frac{1}{1-cos^2x}-1=\frac{1-1+cos^2x}{1-cos^2x}=\frac{cos^2x}{1-cos^2x}\\\\ctgx=\sqrt{\frac{cos^2x}{1-cos^2x}}=\frac{cosx}{\sqrt{1-cos^2x}}](https://tex.z-dn.net/?f=%5Cdisplaystyle+ctg%5E2x%2B1%3D%5Cfrac%7B1%7D%7Bsin%5E2x%7D%5C%5C%5C%5Cctg%5E2x%3D%5Cfrac%7B1%7D%7B1-cos%5E2x%7D-1%3D%5Cfrac%7B1-1%2Bcos%5E2x%7D%7B1-cos%5E2x%7D%3D%5Cfrac%7Bcos%5E2x%7D%7B1-cos%5E2x%7D%5C%5C%5C%5Cctgx%3D%5Csqrt%7B%5Cfrac%7Bcos%5E2x%7D%7B1-cos%5E2x%7D%7D%3D%5Cfrac%7Bcosx%7D%7B%5Csqrt%7B1-cos%5E2x%7D%7D)
Подставим
![\displaystyle ctg(arccos(-1/3))=\frac{cos(arccos(-1/3)}{\sqrt{1-cos^2(arccos(-1/3)}}=\\\\=\frac{-1/3}{\sqrt{1-1/9}}=\frac{-1/3}{\sqrt{8/9}}=-\frac{1}{\sqrt{8}}](https://tex.z-dn.net/?f=%5Cdisplaystyle+ctg%28arccos%28-1%2F3%29%29%3D%5Cfrac%7Bcos%28arccos%28-1%2F3%29%7D%7B%5Csqrt%7B1-cos%5E2%28arccos%28-1%2F3%29%7D%7D%3D%5C%5C%5C%5C%3D%5Cfrac%7B-1%2F3%7D%7B%5Csqrt%7B1-1%2F9%7D%7D%3D%5Cfrac%7B-1%2F3%7D%7B%5Csqrt%7B8%2F9%7D%7D%3D-%5Cfrac%7B1%7D%7B%5Csqrt%7B8%7D%7D)
5600г*7/8=4900г израсходовали на варенье
а 5600-4900=700г осталось