Tìm n € N de bieu thuc 12n^2 -5n -25 la so nguyen to
tim so nguyen n de gtri bieu thuc sau la so nguyen to: 3n3-5n2+3n-5
Tim n nho nhat de n^3-4n^2+4n-1 la so nguyen to
CMR
neu p va \(p^2+8\)la so nguyen to thi \(p^2+2\)cung la so nguyen to
neu p va \(8p^2+1\) la so nguyen to thi 2p+1 cung la so nguyen to
tim so tu nhien n de n^4 +4 la so nguyen to
Bai 10. Chung minh rang:
a) Neu p va p2+8 la cac so nguyen to thi \(p^2+2\)cung la so nguyen to
b) Neu p va 8.p2+1 la cac so nguyen to thi 2.p+1 cung la so nguyen to
Lam nhanh cho minh nha, minh dang can lam gap
tim cac so tu nhien n de gia trị bieu thuc sau la so nguyen to : 5n^3-9n^2+15n-27=0
tim so tu nhien n de n2009+n2008+1 la so nguyen to
Tim so nguyen n de
a, n2 -5
b, n2-4n +3
La cac so chinh phuong