1) 180÷6/23=180×23/6=690
ответ:690 подали заявки
(7а)/(6с)–(49a2+36c2)/(42ac)+(6c–49a)/(7a)=(7a·7a–(49a2+36c2)+6c(6c–49a))/(42ac)=(49a2–49a2–36c2+36c2<span>–294ac)/(42ac)=(–294ac)/(42ac)=–7</span>
(39049/211)*73+1893
(2850577/211)+1893
(2850577+399423)/211
15402.8
4cos^3x-3cosx-cosx=0
4cos^3x-4cosx=0
cos^3x-cosx=0
cosx(cos^2x-1)=0
cosx=0
x1=pi/2+pi*n
cos^2x-1=0
cos^2x=1
cosx=1
x2=0+2pi*n=2pi*n
cosx=-1
x3=pi+2pi*n
Ответ: x1=pi/2+2pi*n; x2=2pi*n; x3=pi+2pi*n