Sagot :
[tex]2y^2 - 5y =-2\\ \\2y^2 - 5y +2=0\\ \\ a=2 , \ b=-5, \ c=2 \\ \\\Delta =b^2-4ac = (-5)^2 -4\cdot2\cdot 2 = 25-16=9 \\ \\y_{1}=\frac{-b-\sqrt{\Delta} }{2a}=\frac{5-\sqrt{9}}{2\cdot 2 }=\frac{5-3}{4}=\frac{2}{4}= \frac{1}{2}[/tex]
[tex]y_{2}=\frac{-b+\sqrt{\Delta} }{2a}=\frac{5+\sqrt{9}}{2\cdot 2 }=\frac{5+3}{4}=\frac{8}{4}= 2\\ \\Answer : \ \left \{ \frac{1}{2},2 \right \}[/tex]
[tex]y_{2}=\frac{-b+\sqrt{\Delta} }{2a}=\frac{5+\sqrt{9}}{2\cdot 2 }=\frac{5+3}{4}=\frac{8}{4}= 2\\ \\Answer : \ \left \{ \frac{1}{2},2 \right \}[/tex]