Question

Determinati multimile
a={x | x€ Z, | x + 1 | =4}
b ={x|x€Z,2x-3|=1}
c={x|x€N, |2-5x|=7}
d={x|x€N, 3=|5-x|}

Answer 1

Mulțimea A
x+1=4
x=3

x+1=-4
x=-5
 A={-4,-5)

Multimea B
2x-3=1
2x=4
x=2

2x-3=-1
2x=2
x=1
B={1,2}

Multimea C
2-5x=7
-5x=5
-x=1  / *(-1)
x=-1

2-5x=-7
-5x=-9
-x=9/5 /*(-1)
x=9/5

C = Ф

Multimea D
5-x=3
x=5-3
x=2

5-x=-3
-x=-3-5
-x=-8 / *(-1)
x=8

D = {2,8}