Question

Tìm \(x\inℕ\)sao cho :

\(2x+19⋮x+3\)

Answer 1

\(2x+19=2.\left(x+3\right)+13⋮x+3\)

\(\Rightarrow x+3\inƯ\left(13\right)=\left\{\pm1,\pm3\right\}\)

\(\Rightarrow x+3=\left\{\pm1,\pm3\right\}\)

\(x=\left\{-2,-4,0,-6\right\}\)

vì x thuộc N => x=0

vậy x=10

Answer 2

\(2x+19=2x+6+13=2\left(x+3\right)+13\)

\(Do2\left(x+3\right)⋮x+3\Rightarrowđể2x+19⋮x+3\)thì \(13⋮x+3\Rightarrow x+3\inƯ\left\{13\right\}=\left\{-13;-1;1;13\right\}\)

Answer 3

sory U(13)={1,-1,13,-13}

mk làm lộn Ư(3) nha 

bn sửa lại đoạn đấy tí