10
{9^x*3^y=1/27⇒3^(2x+y)=-3⇒2x+y=-3
{7^(x-y)=1⇒x-y=0
прибавим
3x=-3
x=-1
-1-y=0
y=-1
Ответ (-1;-1}
6
(2^5)^2x=(2^-3)^(x+3)
2^10x=2^(-3x-9)
10x=-3x-9
10x+3x=-9
13x=-9
x=-9/13
7
(2/3)^x<81/16<br>(2/3)^x<(2/3)^-4<br>x>-4
x∈(-4;∞)
8
2^(2x-x²)>2^-3
2x-x²>-3
x²-2x-3<0<br>x1+x2=2 U x1*x2=-3⇒x1=-1 U x2=3
+ _ +
--------------------(-1)-------------(3)------------------------
x∈(-1;3)
9
(5²)^(x+3)≤5^(-2)*5^x²
5^(2x+6)≤5^(-2+x²)
2x+6≤-2+x²
x²-2x-8≥0
x1+x2=2 U x1*x2=-8
x1=-2 U x2=4
+ _ +
-----------------[-2]----------------[4]-------------------------
x∈(-∞;-2] U [4;∞)