1+2+3+...+n=55
=>n.(n+1):2=55
=>n.(n+1)=55.2=110=10.11(vì n và n+1 là 2 số nguyên liên tiếp)
=>n=10
1+2+3+...+n=55
=>n.(n+1):2=55
=>n.(n+1)=55.2=110=10.11(vì n và n+1 là 2 số nguyên liên tiếp)
=>n=10
Cho bieu thuc B= 7/ n -7
a) So nguyen n phai co dieu kien gi de B la phan so.
b) Tim phan so B biet n = -7
c) Tim cac so nguyen n de B la so nguyen.
bn nao co loi giai chi tiet bai nay mk se tick,vi mk dung dien thoai ko viet dau dc nen cac ban thong cam nha.
Tim n€Z , biet:
a) n+8/n-5 la so nguyen.
b)n2+1/n-6 la so nguyen.
Giup minh voi minh dang can gap .
Lam chi tiet ho minh nha.
tim so nguyen n biet n E Z
3n-2 / n+1
ghi cach giai chi tiet nhe minh se ****
Cong ca tu va mau cua phan so 23/40 voi cung 1 so tu nhien n roi rut gon ta duoc 3/4. Tim so n.
Giai CAN KE den tung chi tiet thi tick. Giai van tat nhu SBT thi nhin nhe !
Tim 3 so nguyen a, b, c thoa man : a+b=-4 ; b+c=-6 ; c+a=12.
Giai can ke tung chi tiet thi tui moi tick cho.
Tich cua hai phan so la 3/7 neu them vao thua so thu nhat 2 don vi thi tich la 13/21. Tim hai phan so do.
Ai giai that chi tiet va de hieu thi minh tick cho.
Cau hoi 1: Chu so tan cung cua 20092008
Cau hoi 2:So tu nhien a va b biet a>b va a+b va a.b la so nguyen to
Cau hoi 3:So phan tu cua tap hop N, {n thuoc tap hop N thoa mman dieu kien 60 chia het cho n}
Cau hoi 4:Chu so tan cung cua 71993
Bai nay minh ko hieu de ne.Ban giai thich va bay minh lam luon nhe:cho M la tap hop cac chu so le,so tap hop con cua M chi gom hai phan tu la?
Tong cua 5 so nguyen to la 198. Tim so nguyen to nho nhat trong 5 so do?
GIAI CHI TIET NHA, MIK TICK CHO
chung minh 2n +5 va 3n + 7 la 2 so nguyen to cung nhau
giai chi tiet nha
ai nhanh like luon