Întrebare
Aflati × € |N pentru care:
a) 2×-1| 25
b) ×+2 | ×+4
a) 2×-1| 25
b) ×+2 | ×+4
Întrebare a fost pusă de: USER8579
63 Vezi
63 Răspunsuri
Răspuns (63)
2x-1 divide 25rezulta 2x-1=1=2x=0=0,2x-1=5=2x=4=2,2x-1=25=2x=24=12 rezulta x apartine(0,2,12)
x+2divide x+4 rezulta x=0
x+2divide x+4 rezulta x=0
[tex]a) \\ 2x-1 ~|~ 25 \\ D_{25} = \{1;~5;~25\} \\ 2x-1=1 ~~ \Longleftrightarrow ~~2x=2 ~~ \Longrightarrow ~~x_1 = \boxed{1} \\ 2x-1=5 ~~ \Longleftrightarrow ~~2x=6 ~~ \Longrightarrow ~~x_2 = \boxed{3} \\ 2x-1=25 ~~ \Longleftrightarrow ~~2x=26 ~~ \Longrightarrow ~~x_3 = \boxed{13} [/tex]
[tex]b) \\ x+2 ~|~x+4 \\ (x+4)-(x+2) = 2~~~\Longrightarrow ~~ (x+4)\vdots (x+2) ~doar~ daca:~ (x+2) \leq 2 \\ x+2 \leq 2 ~\Longleftrightarrow~x \leq 2-2 \Longleftrightarrow x \leq 0 ~~~~~~~Dar~x \in N~\Longrightarrow ~ x=\boxed{0} \\ 0+2 ~| ~0+4 ~~~\Longleftrightarrow~~~ 2~|~4[/tex]