tim x,y de thoa man
a) n^2-4xy+7 la so chinh phuong
b) n^2-3n-1 la so chinh phuong
biet n<20 , tim n sao cho n2 +4n+2017 la so chinh phuong
trinh bay ra nhe cam on
Tim so nguyen n de
a, n2 -5
b, n2-4n +3
La cac so chinh phuong
cho (n*(n+1)*(n+2)):6 la tong cua n so chinh phuong dau tien. khi do tong cua 10 so chinh phuong dau tien
tim mot so chinh phuong co 4 chu so vua la so chinh vua la so lap phuong
Cmr n^2+n+1 khòg la so chinh phuong vs n la so tu nhien lon hon 0
tim n la so tu nhien sao cho n2+2002 la 1 so chinh phuong
tim so tu nhien n de 2^8+2^11+2^n la so chinh phuong
chung minh A = n*(n+1)*(n+2)*(n+3)khong la so chinh phuong voi moi n la so tu nhien
