То будет так я так понимаю потому я тоже 8 класс
![\frac{(n+1)!}{n!} = \frac{(n+1)*n!}{n!} =n+1 ](https://tex.z-dn.net/?f=+%5Cfrac%7B%28n%2B1%29%21%7D%7Bn%21%7D+%3D+%5Cfrac%7B%28n%2B1%29%2An%21%7D%7Bn%21%7D+%3Dn%2B1%0A%0A%0A%0A%0A%0A%0A+)
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![\frac{(n+1)!(n+3)}{(n+4)!}=\frac{1}{(n+2)(n+4)}](https://tex.z-dn.net/?f=++%5Cfrac%7B%28n%2B1%29%21%28n%2B3%29%7D%7B%28n%2B4%29%21%7D%3D%5Cfrac%7B1%7D%7B%28n%2B2%29%28n%2B4%29%7D+)
f`(x)=14x^6+5*1/2Vx=14x^6+5/(2Vx)
1)8=2^3;
2)8*(1/4)^3=(2/4)^3=(1/2)^3=1/8;
3)14*1/4=14/4=7/2;
4)1/8+7/2=(1+7*4)/8=29/8=3 целых5/8 или 3,625