33-x²≥0,
33-x²=0,
(√33-x)(√33+x)=0,
√33-x=0, x₁=√33,
√33+x=0, x₁=-√33,
-(x-√33)(x+√33)≥0,
(x-√33)(x+√33)≤0,
-√33≤x≤√33,
x∈[-√33;√33],
min x=-√33,
max x=√33.
4х + 2:1 + 2х = х - 6
4х - х + 2х = 2:1 - 6
5х = - 5
х = 0