<span>3х+у=4 (1)
х^2-у=14 (2)
(1)+(2)
x</span>²+3x=18
D=9+72=81
x12=(-3+-9)/2=3 -6
x=3
9+y=4
y=-5
x=-6
-18+y=4
y=22
(3 -5) (-6 22)
<span>arccos (sin(-п/4))=arccos(-√2/2)=pi-arccos(√2/2)=pi-pi/4=3pi/4</span>
Log₃(1-6x)=log₃(17-x²)
ОДЗ: 1-6x>0 6x<1 x<1/6 17-x²>0 x²<17 -√17<x<√17 x∈(-√17;1/6).
1-6x=17-x²
x²-6x-16=0 D=100
x₁=-2 x₂=8 ∉ОДЗ
Ответ: x=-2.