<span>ОДЗ
6 - </span>√17 < x < 6 + √17 --><span>
1,87 <x < 10,12
lg(12x - x² - 19) = 2lg(x - 1)
</span><span>lg(12x - x² - 19) = lg(x - 1)^2
</span>12x - x² - 19 = (x - 1)^2
- x^2 + 12x - 19 = x^2 - 2x + 1
- x^2 + 12x - 19 - x^2 + 2x - 1 = 0
- 2x^2 + 14x - 20 = 0 /:(-2)
x^2 - 7x + 10 = 0
D = 49 - 40 = 9
x1 = (7 + 3)/2 = 5 ∈ ОДЗ
x2 = (7 - 3 )/2 = 2 ∈ ОДЗ
Ответ
2; 5
2x(a-b)+a(a-b)=(а-b)(2x+a)
3x+3y+bx+by=(3x+3y)+( bx+by)=3(x+y)+b(x+y)=(x+y)
(3+b)
0,2y(5y²-1)(2y²-1)=
=0,2y(10y⁴-5y²-2y²+1)=
= 0,2y(10y⁴-7y²+1)=
3x-xy-3y+y²=(3x-xy)-(3y-y²)=x(3-y)-y(3-y)=(3-y)(x-y)
ax-ay+cy-cx-x+y=
=(ax-ay)+(cy-cx)-(x-y)=
=a(x-y)+c(y-x)-(x-y)=
=a(x-y)-c(x-y)-(x-y)=
=(x-y)(a-c-1)
Log₃2=a 1/log₂3=a log₂3=1/a
log₀,₅81=2*log₂3⁴=8*log₂3=8/a.
Решение смотри на фотографии