6a^2-5a+1=0,
D=1,
a1=1/3, a2=1/2,
6a^2-5a+1=6(a-1/3)(a-1/2)=(3a-1)(2a-1),
(6a^2-5a+1)/(1-4a^2)=(3a-1)(2a-1)/(-(2a-1)(2a+1))=-(3a-1)/(2a+1)=(1-3a)/(2a+1)
2cos^2 (45* +4a)-1=cos(90*+8a)=-sin8a
4X^2 + Y = 9
8X^2 - Y = 3
-------------------
4X^2 + 8X^2 + Y - Y = 9 + 3
12X^2 = 12
X^2 = 1
X1 = 1
X2 = - 1
-------------------------
4X^2 + Y = 9
Y = 9 - 4X^2
Y = 9 - 4 = 5
-----------------------------
ОТВЕТ ( 1 ; 5 ) ; ( - 1 ; 5 ) нууу или так 4x^2+y=9 12x²=12 x₁=1;x₂=-1<span>
{ + </span>⇒{ ⇒{<span>
</span>8x^2-y=3 y=8x<span>²-3 y=5</span>
<span>(х-4)(х-2)-(х-2)(х+2)=2
(х-2)((х-4)-(х+2)) = 2
(х - 2)(х -4 - х - 2) = 2
(х - 2)(-6) = 2
- 6х + 12 = 2
- 6х = - 12 + 2
- 6х = - 10
х = (- 10) : (- 6)
х = </span>
2 способ
<span>(х-4)(х-2)-(х-2)(х+2)=2
х</span>² - 4х - 2х + 8 - (х² - 4) = 2
х² - 6х + 8 - х² + 4 = 2
- 6х + 12 = 2
- 6х = - 12 + 2
- 6х = - 10
х = (- 10) : (- 6)
х =
Проверка
(5/3-4)(5/3-2) - (5/3 - 2)(5/3 + 2) = 2
(- 7/3) ·( - 1/3) - ((- 1/6) · 11/3 = 2
7/9 + 11/9 = 2
18/9 = 2
2 = 2
Ответ: х =