1)х²-6х+5≥0
х1+х2=6 и х1*х2=5⇒х1=1 и х2=5
+ _ +
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1 5
х∈(-≈;1] U [5;≈)
2)2x/(1+x)≥-1 U 2x/(1+x)≤1
(2x+x+1)/(x+1)≥0 U (2x-1-x)/(1+x)≤0
(3x+1)/(x+1)≥0 U (x-1)/(x+1)≤0
x=-1/3, x=-1 U x=1, x=-1
+ _ + + _ +
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-1 -1/3 -1 1
x∈(-≈;-1) U [-1/3;≈) U x∈(-1;1]⇒x∈[-1/3;1]