tim x dua vao quan he uoc boi:tim so tu nhien x sao cho x-1 la uoc cua 12tim so tu nhien x sao cho 2x+1 la uoc cua 28tim so tu nhien x sao cho x+15 la boi cua x+3tim cac so nguyen x,y sao cho (x+1)(y-2)=3tim so nguyen x sao cho(x+2).(y-1)=2tim so nguyen to x vua la uoc cua 275 vua la uoc cua 180tim so nguyen to x,y biet x+y=12 va UCLL (x:y)=5tim so tu nhien x,y biet x+y=32 va UCLL (x:y)=8tim so tu nhien x biet x chia het cho10; xchia het cho12; x chia het cho15 va 100<x<150tim so x nho nhat khac 0b...
Đọc tiếp
tim x dua vao quan he uoc boi:
tim so tu nhien x sao cho x-1 la uoc cua 12
tim so tu nhien x sao cho 2x+1 la uoc cua 28
tim so tu nhien x sao cho x+15 la boi cua x+3
tim cac so nguyen x,y sao cho (x+1)(y-2)=3
tim so nguyen x sao cho(x+2).(y-1)=2
tim so nguyen to x vua la uoc cua 275 vua la uoc cua 180
tim so nguyen to x,y biet x+y=12 va UCLL (x:y)=5
tim so tu nhien x,y biet x+y=32 va UCLL (x:y)=8
tim so tu nhien x biet x chia het cho10; xchia het cho12; x chia het cho15 va 100<x<150
tim so x nho nhat khac 0b biet x chia het cho 24 va 30
40 chia het cho x . 56 chia het cho x va x>6
\(2xy-3x+y=2\)
\(\Leftrightarrow x\left(2y-3\right)+\frac{1}{2}\left(2y-3\right)=\frac{4}{3}\)
\(\Leftrightarrow6x\left(2y-3\right)+3\left(2y-3\right)=8\)
\(\Leftrightarrow\left(2y-3\right)\left(6x+3\right)=8\)
Lập bảng xét ước là xong bạn nhé !
2xy-3x+y=2
<=> 4xy-6x+2y=4
<=> 2y(2x+1)-3(2x+1)=1
<=> (2x+1)(2y-1)=1
\(\Rightarrow2x+1;2y-1\inƯ\left(1\right)=\left\{-1;1\right\}\)
TH1: \(\hept{\begin{cases}2x+1=-1\\2y-1=-1\end{cases}\Leftrightarrow\hept{\begin{cases}2x=-2\\2y=0\end{cases}\Leftrightarrow}\hept{\begin{cases}x=-1\\y=0\end{cases}}}\)
TH2: \(\hept{\begin{cases}2x+1=1\\2y-1=1\end{cases}\Leftrightarrow\hept{\begin{cases}2x=0\\2y=2\end{cases}\Leftrightarrow}\hept{\begin{cases}x=0\\y=1\end{cases}}}\)
Vậy có 2 cặp (x,y) thỏa mãn yêu cầu đề bài (-1;0);(0;1)