Cho p va 8p -1 la so nguyen to . Chung minh 8p+1 la hop so
cho p va p+8 la so nguyen to(p>3).chung minh rang:8p-1 la hop so
cho p va 10p+1la so nguyen to(p>3).chung minh rang:5p+1la hop so
cho so nguyen to p va mot trong hai s 8p+1 va 8p-1 la so nguyen to ,so con lai la so nguyen to hay hop so?
Cho P va 8P-1 la so nguyen to (p>3)
Hoi 8P+1 la so nguyen to hay hop so.
cho p la so nguyen to lon hon 3
a] chung to rang p 6k+1 hoac 6k+5
b] biet 8p +1 la so nguyen to chung minh 4p+1 la hop so
bai 3 cho p la so nguyen to lon hon 3
A, chung to p co dang 6k+1 hoac 6k+5
B, cho p va 8p-1 la so nguyen to. chung to 8p+1 la hop so
bai 4
A, tim a va b biet rang a.b=320 va BCNN(a,b)=160
B, tim so tu nhien a nho nhat co 3 chu so sao cho khi chia a cho 11 du 5 va chia cho 13 thi du 8
cho P>5 la so nguyen to va 2P+1 cung la 1 so nguyen to Chung minh 4P+1 la hop so
Cho P la so nguyen to lon hon 3 va 5p+1 cung la so nguyen to. Chung minh rang 7p+1 la hop so
