gấp Tìm số nguyên x biết (x+14)chia hết(x+11) 30/11/2021 Bởi Julia gấp Tìm số nguyên x biết (x+14)chia hết(x+11)
$x+14 \vdots x+11$ $⇔(x+11)+3 \vdots x+11$ $⇔3 \vdots x+11$ $⇔x+11 ∈ \{-1,1,-3,3\}$ $⇔x ∈\{-12,-10,-14,-8\}$ Bình luận
$x+14$ $⋮$ $x+11$ $⇒(x+11)+3$ $⋮$ $x+11$ Vì $x+11$ $⋮$ $x+11$ $⇒3$ $⋮$ $x+11$ $⇒x+11∈Ư(3)=\{±1;±3\}$ $⇒x∈\{-8;-10;-12;-14\}$ Bình luận
$x+14 \vdots x+11$
$⇔(x+11)+3 \vdots x+11$
$⇔3 \vdots x+11$
$⇔x+11 ∈ \{-1,1,-3,3\}$
$⇔x ∈\{-12,-10,-14,-8\}$
$x+14$ $⋮$ $x+11$
$⇒(x+11)+3$ $⋮$ $x+11$
Vì $x+11$ $⋮$ $x+11$
$⇒3$ $⋮$ $x+11$
$⇒x+11∈Ư(3)=\{±1;±3\}$
$⇒x∈\{-8;-10;-12;-14\}$