Cho 2014 so nguyen, trong do tich cua 3 so bat ki luon la 1 so nguyen am.chung to rang tich cua 2014 so nguyen do la mot so nguyen duong
Ai nhanh minh tick luon
cho M =(-a+b)-(b+c-a)+(c-a).Trong do b,c la so nguyen am hoac duong.a la so nguyen am.Chung minh M>0
a. cho 2017so nguyen trong do 7 so bat ki luon co tong am. hoi tong cua2017 so do la am hay duong?
b. cho 2017 so nguyen trong do 7 so bat ki luon co tich am. hoi tich cua 2017 so do la am hay duong? moi so nguyen do la am hay duong
dien dung sai
a/tich cua hai so nguyen duong la mot so nguyen duong
b/tich cua hai so nguyen am la mot so nguyen am
c/tich cua 2 so nguyen cung dau luon lon hon moi so do
d/tich cua hai so nguyen khac dau luon nho hon moi so do
e/neu tich hai so nguyen la mot so nguyen duong thi hai so do deu la so nguyen duong
f/neu tich hai so nguyen la mot so nguyen am thi hai so do deu la so nguyen am
cho 16 so nguyen trong do tich cua 3 o bat ky luon la mot so nguyen am. chung to rang tich cua 16 so nguyen do la mot so nguyen duong
minh can gap!
cho 2014 so nguyen trong do tich cua 3 so bat ky luon la 1 so nguyen am chung to rang tich cua 2014 so nguyen do la 1 so nguyen duong
cho A = ( a + 2002 )(a+ 2003) , B= ab(a+b) chung minh rang voi moi so nguyen a va b , A va B luon la boi cua 2
Cho bieu thuc A= a3 + 2a2 - 1 / a3 + 2a2 + 2a + 1
a, Rut gon bieu thuc
b,Chung minh rang neu a la so nguyen thi gia tri cua bieu thuc tim duoc o cau a la mot so nguyen,la phan so toi gian
chung to rang voi moi so tu nhien N gia tri cua 2 bieu thuc 7n+10 va 5n+7 luon la 2 so nguyen to cung nhau