Question

14:31
Dterminati valorile
intregi ale lui x pentru care:

a) 8
___ e Z
x

b) 6
__ e N
x
c) -18
___ e Z
2-x

d) 12
__ e N
3-x

e) 15
___ e N
2x-1

f) 21
___ e Z
2x+1​

Answer 1

Răspuns:

Explicație pas cu pas:

a) x ∈ {-1, 1, -2, 2, -4, 4, -8, 8}

b) x ∈ {1, 2, 3, 6}

c) 2-x ∈ {-1, 1, -2, 2, -3, 3, -6, 6, -9, 9, -18, 18} → -x ∈ { -3, -1, -4, 0, -5, 1, -8, 4, -11, 7, -20, 16} → x ∈ {3, 1, 4, 0, 5, -1, 8, -4, 11, -7, 20, -16}

d) 3-x ∈ {1, 2, 3, 4, 6, 12} → -x ∈ { -2, -1, 0, 1, 3, 9} → x ∈ {2, 1, 0, -1, -3, -9}

e) 2x-1 ∈ {1, 3, 5, 15} → 2x ∈ { 2, 4, 6, 16} → x ∈ { 1, 2, 3, 8}

f) 2x+1 ∈ {-1, 1, -3, 3, -7, 7, -21, 21} → 2x ∈ {-2, 0, -4, 2, -8, 6, -22, 20} → x ∈ { -1, 0, -2, 1, -4, 3, -11, 10}