-(x²-7x-9)+1≥2(x²-7x-9)² x²-7x-9=a -a+1≥2a² 2a²+a-1≤0 D=1+8=9 a1=(-1-3)/4=-1 U a2=(-1+3)/4=0,5 a≥-1⇒x²-7x-9≥-1 x²-7x-8≥0 x1+x2=7 U x1*x2=-8⇒x1=-1 U x2=8 x≤-1 U x≥8 a≤0,5⇒x²-7x-9≤0,5 x²-7x-9,5≤0 D=49+38=87 x1=(7-√87)/2 U x2=(7+√87)2 (7-√87)/2 ≤x≤(7+√87)2 x∈[(7-√87)/2;-1] U [8;(7+√87)/2]
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-(x²-7x-9)+1≥2(x²-7x-9)²x²-7x-9=a
-a+1≥2a²
2a²+a-1≤0
D=1+8=9
a1=(-1-3)/4=-1 U a2=(-1+3)/4=0,5
a≥-1⇒x²-7x-9≥-1
x²-7x-8≥0
x1+x2=7 U x1*x2=-8⇒x1=-1 U x2=8
x≤-1 U x≥8
a≤0,5⇒x²-7x-9≤0,5
x²-7x-9,5≤0
D=49+38=87
x1=(7-√87)/2 U x2=(7+√87)2
(7-√87)/2 ≤x≤(7+√87)2
x∈[(7-√87)/2;-1] U [8;(7+√87)/2]