25 получится )
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7м=700см
значит,700-7=693
ответ:на 693
11/9 : 11/3 + 22/5: (7/10+13/5)-(3/17-33/17:187/17= 11/9:33/9+22/5:(7/10+26/10)-(3/17-33/187)= 11/33+44/10:33/10-0=11/33+44/33=55/33=5/3= 1 2/3
42 л-по 24 р|
16 кг-по 40 р| Ск.-?руб.
Решение:
1)42*24=1008руб- за молоко
2)16*40=640руб.-за творог
3)1008+640=1648руб-выручил Матроскин за свой товар
(cos23π/12-sin11π/12)(sin17π/12-cos19π/12)
=(cos(2π-π/12)-sin(π-π/12))*
(sin(π+5π/12)-cos(2π-5π/12)=
(cosπ/12-sinπ/12)(-sin5π/12-cos5π/12)=
(cosπ/12-sinπ/12)(-sin(π/2-π/12)-
cos(π/2-π/12))==
(cosπ/12-sinπ/12)(-1)(cosπ/12+sinπ/12)=
-(cos²π/12-sin²π/12)=-cosπ/6=-√3/2