👤

Sa se determine m € R a.î. distanta dintre punctele A (2,m)si B (m,-2) sa fie 4

Răspuns :

AB=[tex] \sqrt{(xA-xB)^2+(yA-yB)^2} =4 =\ \textgreater \ (xA-xB)^2+(yA-yB)^2=16[/tex]
Am ridicat la patrat.
(2-m)²+(m+2)²=16
4-4m+m²+m²+4m+4=16
<=>2m²+8=16=>2m²=8|:2 =>m1=+2 si m2=-2