=> 3/1.4+3/4.7+.....+3/97.100 = 0,99x/2014
=> 1-1/4+1/4-1/7+....+1/97-1/100 = 0,99x/2014
=> 0,99x/2014 = 1-1/100 = 99/100
=> x = 99/100 : 0,99/2014 = 2014
Vậy x = 2014
Tk mk nha
1*4+4*7+7*10+...+97*100
2/1×4+2/4×7+2/7×10+... +2/97×100
Tính
A=1+3+5+...+101
B=1+4+7+10+...+100
C=100-99+98-97+...+2-1
D=1+4+5+9+14+...+60+97
E=1+2-3-4+5+6-7-8+...-299-300+301+302
A=1-2-3-4=5-6-7-8+9-10-11-12+...+97-98-99-100
B=1+2-3-4+5+6-7-8+....+97+98-99-100
Tính tổng:A=2/1×4+2/4×7+2/7×10+...+2/97×100
tinh tong : 2\1*4+2\4*7+2\7*10+......+2\97*100
*+Tính nhanh:D=2/1*4+2/4*7+2/7*10+...+2/97*100
(1-3/4)(1-3/7)(1-3/10)(1-3/13)....(1-3/97)(1-3/100) = ?
Tính tổng : B = 2 /1 *4 +2 / 4*7 +2/7*10 +...+2/97 *100
