Question

D ( x^{4}-2 x^{2}-3 leq 0 )
et ( x^{2}=y )
( y^{2}-2 y-3 leq 0 )
( y^{2}-3 y+y-3 leq 0 )
( y(y-3)+1(y-3) leq 0 )
( begin{array}{rl}(y+1)(y-3) leq 0 & y leq-1 quad text { of } & y leq 3 x^{2} leq-1 & x^{2} leq 3 text { (not possible) } & Rightarrow-sqrt{3} leq x leq sqrt{3} x=[-sqrt{3}, sqrt{3}]end{array} )

# Solve x* – 2x²–350 (1) [-13, 13] (2) (-13, 13) (3) 11,3] (4) · (41,3) (-1,3)

Solution