<span> log11(x+4)+log11(x+7)=log11(7+x) одз х+4>0,х>-4 х+7>0,х>-7</span>
1)
D=25+56=81
x1=(-5-9)/4=-3,5
x2=(-5+9)/4=1
x∈(-∞;-3,5) U (1;∞)
2)
(3x-4)/(2x+6) -1>0
(3x-4-2x-6)/(2x+6)>0
(x-10)/(2x+6)>0
x=10 U x=-3
x∈(-∞;-3) U (10;∞)
Lg(x)=lg(m)+2lg(n)-3lg(a)
lg(x)=lg(mn^2/a^3)
x=mn^2/a^3
1)
![y ^{'} =4*sin(x)+cos(x)](https://tex.z-dn.net/?f=y++%5E%7B%27%7D+%3D4%2Asin%28x%29%2Bcos%28x%29)
подставляем пи/2,получаем 4
ответ 4
2)
![y ^{'} = \frac{3*(1-2*x)}{x-x^{2} }](https://tex.z-dn.net/?f=y+%5E%7B%27%7D+%3D+%5Cfrac%7B3%2A%281-2%2Ax%29%7D%7Bx-x%5E%7B2%7D+%7D+)
8 × (1/4)² + 14 × 1/4 = 8 × 1/16 + 14/4 = 8/16 + 14/4 = 0,5 + 3,5 = 4