Question

varog aflati multimea B​

Answer 1

Hei! :)

• B={x € Z |3x-7/2x+3 € Z}

3x-7/2x+3 € Z

=> (2x+3) | (3x-7)

    (2x+3) | -2(3x-7)

    (2x+3) | (-6x+14)     (1)

(2x+3) | 3(2x+3)

(2x+3) | (6x+9)         (2)

=> (1) si (2) => (2x+3) | [(-6x+14)+(6x+9)]

(2x+3) | 23

=> (2x+3) | {-23, -1,1,23}

Cazul 1: 2x+3= -23  => x=-13

Cazul 2: 2x+3=-1 =>    x=-2

Cazul 3: 2x+3=1 => x= -1

Cazul 4: 2x+3=23 => x=10

=> x∈{-13, -2, -1, 10}