Question

Va rog frumos problemele 23 ; 24 si 25 .
Multumesc .

Answer 1

Sper că te am ajutat...in ce clasa esti? Eu sunt in cls a 6a

Answer 2

23.

{x;y}d.p.{2;9}

=>x/2=y/9=k

x=2k; y=9k

inlocuim x si y in fractia data:

(2•2k+6•9k)/(25•2k-9k)=58/41

(4k+54k)/(50k-9k)=58/41

58k/41k=58/41; simplificam cu k

=> 58/41=58/41, este adevarat

=>(2x+6y)/(25x-y)=58/41  este adevarata daca {x; y}d.p.{2; 9}

24.

{a;b;c;d}d.p.{5; 4; 2; 3}  si bc=4d

a/5=b/4=c/2=d/3=k

=> a=5k; b=4k; c=2k; d=3k

b•c=4k•2k=8k²

8k²=4•3k     /:4k

2k=3; => k=3/2

a=5•3/2=15/2

b=4•3/2=6

c=2•3/2=3

d=3•3/2=9/2

a+b+c+d=15/2 +6+3 +9/2=(15+9)/2+9=12+9=21

D21={-21; -7; -3; -1; 1; 3; 7; 21};  multimea divizorilor intregi

D21={1; 3; 7; 21};  multimea divizorilor naturali