1) Cho bieu thuc : A= 2n +1 /n-3 + 3n-5/ n-3 -  4n-5 /n-3

a)Tim so nguyen n de A nhan gia tri nguyen 

b) Tim n de A la phan so toi gian

Tim so tu nhien n de phan so A=\(\frac{2n+1}{n-3}+\frac{3n-5}{n-3}-\frac{4n-5}{n-3}\)

a/Tim n de A nhan gia tri nguyen

b/Tim n de A la phan so toi gian 

cho bieu thuc :A=2n+1/n-3+3n-5/n-3-4n-5/n-3.a, tim n de a nhan gia tri nguyen .b,tim n de a la phan so toi gian

cho bieu thuc :A=2n+1/n-3+3n-5/n-3-4n-5/n-3.a, tim n de a nhan gia tri nguyen .b,tim n de a la phan so toi gian

Tim so nguyen n de phan so 2n+3/7n+9 khong toi gian

tim so nguyen duong nho nhat de khi nhan no voi moi mot trong cac phan so toi gian 3/4, -5/11, 7/12 deu duoc tich la nhung so nguyen

cho bieu thuc:P= 2n+1/n-3 + 3n-5/n-3 + 4n-5/n-3

a) tim n de P nhan gia tri nguyen

b)tim n de P la phan so toi gian

Tim so nguyen duong nho nhat de khi nhan no voi moi mot phan so toi gian sau deu duoc tich la nhung so nguyen:

5/6         -7/15        11/21

tim so nguyen to n de n/74 la phan so toi gian. cac ban gup minh nhe