So so hang la :
( 4851 -1) : 2 + 1 = 2426
Tong la :
( 4851 + 1) . ( 2426 : 2 ) = 5885476
Vay 1+3+6+....+4851=5885476
So so hang la :
( 4851 -1) : 2 + 1 = 2426
Tong la :
( 4851 + 1) . ( 2426 : 2 ) = 5885476
Vay 1+3+6+....+4851=5885476
Tính nhanh hộ mình câu này với :
1+3+6+10+...+4851/1*98+2*97+3*96+...+97*2+98*1
Tính tổng : A=38/25 + 9/10 - 11/15 + 13/21 - 15/28 + 17/36 - ................+197/4851-199/4950
Tim y biet:
32.4 x y + 68.6 x y - y = 4851
Tim y:
32.4 x y + 68.6 x y - y = 4851
A = \(\dfrac{28}{25}\) + \(\dfrac{9}{10}\) - \(\dfrac{11}{15}\) + \(\dfrac{13}{21}\) - \(\dfrac{15}{28}\) + \(\dfrac{17}{26}\) - ... + \(\dfrac{197}{4851}\) - \(\dfrac{199}{4950}\)
d/ khó lắm đó nha. ai biết minh tích
38/25 + 9/10 - 11/15 + 13/21 - 15/28 + 17/36 - ............. + 197/4851 - 199/4950.
2. ( x + 1 ) + ( x + 4 ) + ( x + 7 ) + ......... + ( x + 28 ) = 155
Tính tổng \(A=\frac{38}{25}+\frac{9}{10}-\frac{11}{15}+\frac{13}{21}-\frac{15}{28}+\frac{17}{36}-...+\frac{197}{4851}-\frac{199}{4950}\)
Tính tổng : A=38/25 + 9/10 - 11/15 + 13/21 - 15/28 + 17/36 - ................+197/4851-199/4950
\(tính\)\(nhanh\)\(:\)
\(\frac{38}{25}+\frac{9}{10}-\frac{11}{15}+\frac{13}{21}-...+\frac{197}{4851}-\frac{199}{4950}\)