tinh E= 1x3+3x5+5x7+....+97x99+99x101
tinh
S = 2/1x3-4/3x5+6/5x7-8x7x9+...-96/95x97+98/97x99
1x3+3x5+5x7+...+99x101
1x3+3x5+5x7+...+97x99
tính : 1x3 +3x5 +5x7 +....+99x101
2\1x3+2\3x5+2\5x7+...+2\99x101
tính nhanh
1x3 + 3x5 + 5x7 + 7x9 + ......... + 97x99
tinh gia tri bieu thuc
S = 2/1x3-4/3x5+6/5x7-8/7x9+.....-96/95x97+98/97x99
tinh
a)A=1x2+2x3+3x4+............+99x100
b)B=1x3+3x5+5x7+............97x99
c)C=1x2x3+2x3x4+..............98x99x100
