Réponses

  • Utilisateur Brainly
2013-10-28T10:47:37+01:00
x+1/x = 5
x²-5x+1=0
x=(5-rac(21))/2 ou x=(5+rac(21))/2

x^4 -6x²+5<0 
(x²)²-6x²+5<0
1<x²<5
1<x<rac(5)

x+1<= 4/(x-2)
((x+1)(x-2)-4)/(x-2) <=0
(x²-x-6)/(x-2) <= 0
(x+2)(x-3)/(x-2) <=0
x<=-2 ou x>=3

2x^3-5x+3x=0
x(2x²-2)=0
x=0 ou x=-1 ou x=1