a mu 4 cong a mu 2 coong 1 cong the la mot so nguyen to hay ko
Biet rang 3n cong 1 va 5n cong 4 (n thuoc N ) la 2 so khong nguyen to cung nhau . Tim UCLN cua 2 so tren
tai sao ta co the noi Cong hai so nguyen la truong hop rieng cua cong hai phan so ? choVD
n>2.CMR NEU N CHIA HET CHO 3 THI N MU 2 TRU 1 VA N MU 2 CONG 1 KO DONG THOI CUNG LA SO NGUYEN TO
Tim so nguyen to a de 4a cong 11 la so nguyen to nho hon 30
Tim so nguyen to p de p cong 10 va p cong 20 cung la so nguyen to
Cho 3 so nguyen p ; p cong 2014.k;p cong 2015.k la cac so nguyen to lon hon 3 va p chia cho 3 du 1.Chung minh rang k chia het cho 6
chung to rang tong sau co gia tri la 1 so chinh phuong
1mu3 cong 2 mua3 cong .....cong 10 mu3
1.Tong (hieu) sau la so nguyen to hay hop so
a/5.6.7+8.9 b/5.7.9.11-2.3.7 c/5.7.11+13.17.19 d/4253+1422
2.Hai so nguyen to sinh doi la hai so nguyen to hon kem nhau 2 don vi.Tim hai si nguyen to sinh doi nho hon 50.
3.Cho biet:Neu do tu nhien a(lon hon 1)khong chia het cho moi so nguyen to p ma binh phuong ko vuot qua a(tuc la p2 lon hon hoac bang aĐ thi a la so nguyen to.Dung nhan xet tren cho biet so nao trong cac so 59;121;179;197;217 la so nguyen to?
4.a/So 2009 co la boi cua 41 ko?
b/Tu 2000 den 2020 chi co 3 so nguyen to la 2003;2011;2017.Hay giai thich tai sao cac so le khac trong khoang tu 2000 den 2020 deu la hop so.
5.Goi a=2 . 3 . 4 . 5 . .... . 101. Co phai 100 so tu nhien lien tiep sau deu la hop so ko?
a+2,a+3,a+4,...,a+101.
ai dung kik cho,giup mk nha,ai biet lam bai nao thi lam cung dc,lm het cang tot