Chung to rang phan so sau toi gian voi moi n thuộc N
2n+1/2n(n+1)
Lam on do ai lam dc minh cho 6 tich
Cau 1: Chung minh rang cac phan so sau la phan so toi gian voi moi so nguyen?
a, 8n + 5 phan 6n + 4 b, n + 1 phan 2n + 3 c, 2n + 3 phan 3n + 5
Cau 2: Tim tat ca cac so tu nhien n de phan so sau la toi gian
a, n + 13 phan n - 2. b, 18n + 3 phan 21n + 7
Ai giai day du va nhanh thi mk se tick cho
2015 ×(2015-1)×(2015-2)×(2015-3)×...(2015-k)
Voi k€ N va tich trên co dung 2016 thua so.
May ban giup mink nhanh chóng thi mink tick cho nha.
Chung minh rang phan so sau toi gian voi moi n thuoc N 2n+1/2n(n+1)
a, Chung minh rang 5m+3 va 3m+2 la 2 so nguyen biet rang 1 so bang 10 ngen to cung nhau voi m la so nguyen to bat ky.
b,Tim 1 bo ba so nguyen to biet rang 1 so bang 10 phan tram tong cua 3 so can tim
Ai lam nhanh nhat minh tick cho
Cho phan so \(\frac{n+1}{n-3}\left(n\in Z,n\ne3\right)\)tim n de tu va mau chi co uoc chung la 1 va -1
CAC BAN GIUP MINH NHE !!!!!!!!!!!!!! MINH TICK CHO NEU AI LAM DUNG+NHANH+CACH LAM !!!!!!!!!!!!!!!!!!!!!!!!!!
cac phan so \(\frac{n+1}{2n+3}\)va\(\frac{2n+1}{2n+3}\)la cac phan so toi gian voi moi so nguyen n khac -1
Chung minh rang moi phan so dang n+1/2n+3 ( n thuoc N ) deu la phan so toi gian.
Tim so tu nhien co hai c/s , cac chu so giong nhau , biet rang so do chia het cho 2 va chia cho 5 thi du 3
cac ban giup mink voi toi mink can rui , ai nhanh mink se tick va ket ban