tim so co 4 chu so abcd, biet rang abd la so chinh phuong, neu cong them 72 don vi thi duoc mot so chinh phuong
tim so chinh phuong co 4 chu so ,biet rang neu lay chu so hang nghin tru di 3, chu so hang don vi cong them 3 thi duoc so moi cung la so chinh phuong
Cho a la so co 2 chu so tim a biet rang tong 2 chu so cua a cong them binh phuong cua tong 2 chu so do se duoc a.
tu 10 chu so :0,1,2,3,4,.....,9 hay ghep thanh 5 so co 2 chu so roi cong chung lai
a,tim gia tri lon nhat cua tong
b,tim gia tri nho nhat cua tong
chung minh tich cua 4so tu nhien lien tiep cong 1 la so chinh phuong
CO BAO NHIEU SO TU NHIEN CO 2 CHU SO SAO CHOSO DO CONG VOI SO DO DUOC VIET THEO THU TU NGUOC LAI CHO KET QUA LA 1 SO CHINH PHUONG
chung minh rang neu a,b la tong cua2 so chinh phuong thi ab cung la tong cua 2 so chinh phuong
tim so tu nhien co tinh chat:so do cong 25 va so do tru 12 deu co ket qua la so chinh phuong
tim 2 phan so co tu = 1, cac mau duong, biet rang tong cua 2 phan so ay cong voi tich cua chung = 1/2
