Răspuns:
a) x ∈ {0 ; 3 ; 5 ; 6 ; 9}
b) x ∈ {0 ; 1 ; 2 ; 3}
Explicație pas cu pas:
a) 3x/45
x = 0 => 30/45⁽⁵ = 6/9 = 2/3
x = 3 => 33/45⁽³ = 11/15
x = 5 => 35/45⁽⁵ = 7/9
x = 6 => 36/45⁽³ = 12/15⁽³ = 4/5
x = 9 => 39/45⁽³ = 13/15
x ∈ {0 ; 3 ; 5 ; 6 ; 9}
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5/(x+1) > 1 =>
x = 0 => 5/1 > 1
x = 1 => 5/2 > 1
x = 2 => 5/3 > 1
x = 3 => 5/4 > 1
x ∈ {0 ; 1 ; 2 ; 3}