Tính B = 1/2+(1/2)^2+ (1/2)^3+(1/2)^4+....+(1/2)^98+(1/2)^99+(1/2)^99 Ta được B=
Tính tổng:
a) A= 1^2*2 + 2^2 *3 + 3^2*4 +...+ 99^2*100
b) B= 1*2^2 + 2*3^2 + 3*4^2 +...+ 99*100^2
c) C= 1^3 + 2^3 + 3^3 +...+ 99^3
1.Tính
B=1/2+2/2^2+3/2^3+4/2^4+.....+99/2^99+100/2^100
Tính (1/2)^2+(1/2)^3+(1/2)^4+...+(1/2)^98+(1/2)^99+(1/2)^99
1. tính nhanh:
a) 99^3+1+3.(99^2+99)
b) 10,2+9,8-9,8.0,2+10,2^2-10,2.0,2
b=1/2+(1/2)^2+(1/3)^3+....++(1/2)^98+(1/2)^99+(1/2)^99
tính B=1/2+(1/2)^2+(1/2)^3+(1/2)^4+.........+(1/2)^99 =>B=..........
a, Cho A= 1/99 + 2/98 + 3/47 + .......... + 98/2 + 99/1
B= 1/2 + 1/3 + 1/4 + ..........+ 1/99 + 1/100
Tính B/A
b, Cho A= 1/49 + 2/48 + 3/47 +.......+ 48/2 +49/1
B= 1 + 2/3 + 2/4 +......+ 2/49 + 2/50
Tính A/B
tính nhanh (1+2+3+...+99+100).(1/2-1/3-1/7-1/9)(63.1,2-21.3,6)/1-2+3-4+...+99-100