8.
g(y) = √(3y²-y-14)
y²-9
{y²-9≠0
{3y²-y-14≥0
{y≠3
{y≠-3
{3y²-y-14≥0
3y²-y-14≥0
3y²-y-14=0
D=1+4*3*14=1+168=169
y₁=1-13=-2
6
y₂=1+13=14= 7 = 2 ¹/₃
6 6 3
+ - +
--------- -2 ------------ 2 ¹/₃ -----------
\\\\\\\\\ \\\\\\\\\\\\
x∈(-∞; -2] U [2 ¹/₃; +∞)
D(g)=(-∞; -3)U(-3; -2]U[2 ¹/₃; 3) U (3; +∞) - область определения
9. 4x-x²≤3
4x-x²-3≤0
x²-4x+3≥0
x²-4x+3=0
D=16-12=4
x₁=4-2=1
2
x₂=4+2=3
2
+ - +
---------- 1 ------------- 3 --------------
\\\\\\\\\ \\\\\\\\\\\\\\\\\
x∈(-∞; 1]U[3; +∞)
х={1; 3; 4; 5;......R}