у=√(х²-8х-84)
ОДЗ х²-8х-84 ≥0
D=64+336=400 √D=20
x₁= (8+20)/2=14
x₂=(8-20)/2= - 6
+ - +
-614
x∈ (-∞; -6)∪(14; +∞)
у=√(х²-8х-84)
ОДЗ х²-8х-84 ≥0
D=64+336=400 √D=20
x₁= (8+20)/2=14
x₂=(8-20)/2= - 6
+ - +
-614
x∈ (-∞; -6)∪(14; +∞)