Ta có :
\(\frac{3n+4}{n-1}=\frac{3n-3}{n-1}+\frac{7}{n-1}=3+\frac{7}{n-1}\) nguyên
<=> n - 1 \(\in\) Ư(7) = {-7; -1; 1; 7}
<=> n \(\in\) {-6; 0; 2; 8}
Tim cac so nguyen x,y thoa man:
\(\left|x-7\right|+\left|3-x\right|=\frac{12}{\left|y+1\right|+3}\)
tap hop cac so nguyen x thoa man \(\frac{\left(x-1\right)\left(x+5\right)}{\left(x-1\right)\left(2x+6\right)}=1\)
tim so nguyen x thoa man:\(\frac{-1}{8}\) < \(\frac{x}{8}\)<\(\frac{1}{4}\)
CMR : neu 3 so a ; a+n ; a+2n deu la cac so nguyen to lon hon 3 thi n chia het cho 6
so so nguyen x thoa man \(\left(x+4\right)_{ }\) chia het \(\left(x+1\right)\)
tim n thuoc N sao cho A=n/n^2-n+1 la so nguyen
tim gia tri lon nhat cua bieu thuc :
a) C= 5+ 15/ 4 I 3x+7 I +3
b) D= 2 I 7x+5I +11/ I 7x+5I +4
so cap so nguyen x,y thoar man dieu kien \(\frac{3}{x}+\frac{y}{3}=\frac{5}{6}\)
tim x;y nguyen thoa man
3x+7=y(x-3