Х = у + 4
<span>Подставляем во второе уравнение </span>
<span>24 * (1/(у+4) + 1/у) = 5 </span>
<span>24 * (2у + 4) / (y^2 + 4y) = 5 </span>
<span>48y + 96 = 5y^2 + 20y </span>
<span>5y^2 - 28y - 96 = 0 </span>
<span>y1 = 8; х1 = 12 </span>
<span>у2 = -2,4; х2 = 1,6</span>
1) [6;10]
-----®--------------------®----- >
6 xxxxxxxxxxxxx 10
2) [-5;-1]
------®--------®---------------------- >
-5 xxxx -1
3) [-9;3)
-----®-------------------------o---------- >
-9 xxxxxxxxxxxxxxxx 3
4 (-1;7]
----------------o----------------------------®------ >
-1 xxxxxxxxxxxxxxxxxx 7
5) (-∞;15)
-------------o----------------------------------- >
Xxxxxxxxx 15
6) (8;+∞)
---------------------------o-------------------------- >
8 xxxxxxxxxxxxxxxxx
7) (-∞; 2]
--------------------------®--------------------------- >
Xxxxxxxxxxxxxxxxxx 2
8) [-3;+∞)
----------------------------------®------------------------------- >
-3 xxxxxxxxxxxxxxxxxxxx
надеюсь понятно.удачиии!!!!
2
а)
б)
в)
г)
3
а)
б)(1/a²-1/b²)*a²b²=(b²-a²)/a²b² * *a²b²=b²-a²
в)
4
5
(x+y)/(∛x+∛y)=(∛x+∛y)(∛x²-∛(xy)+∛y²)/(∛x+∛y)=∛x²-∛(xy)+∛y²
Наибольший отрицательный корень: х=-π/3