Bai 1
vì (30-11):4=4.75 nen a <5
nguyên tố bé hơn 5 chỉ có 2 và 3 nên a =2;3
Vậy a ={2;3}
Bai 1
vì (30-11):4=4.75 nen a <5
nguyên tố bé hơn 5 chỉ có 2 và 3 nên a =2;3
Vậy a ={2;3}
tim cac so nguyen to a de 4a +11 la so nguyen to nho hon 30
Bai 1:tim so nguyen P biet P+2va P+4 deu la nguyen to
bai 2: tong 2^100×7×11+81^3 la nguen to hay hop so ( giai thich)
Bai 3: tim so nguyen to P de P +2,p+6,P+8 deu la cac so nguyen to
Tim so nguyen to a de 4a cong 11 la so nguyen to nho hon 30
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
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
a, tim n de n^2 + 2006 la mot so chinh phuong
b, Cho n la so nguyen to lon hon 3. Hoi n^2 + 2006 la so nguyen to hay hop so.
Tim cac so nguyen to p de 4p+9 la so nguyen to nho hon 40.
Tim cac so nguyen to p de 4p +9 la so nguyen to nho hon 40.
cho p la so nguyen to lon hon 3. Biet 8p+1 va p deu la so nguyen to (p lon hon 3).Hoi p+100 la so nguyen to hay hop so