4A=4.[1.2.3 + 2.3.4 + 3.4.5 + 4.5.6 + . . . . . . + 48.49.50]
4A=1.2.3.4 +2.3.4.4 +3.4.5.4 +4.5.6.4 +.........+48.49.50.4
4A=1.2.3.4 +2.3.4.(5-1) + 3.4.5.(6-2) +4.5.6(7-3)+....+ 48.49.50(51-47)
4A=1.2.3.4 +2.3.4.5 --1.2.3.4 + 3.4.5.6--2.3.4.5 + 4.5.6.7-3.4.5.6+....+ 48.49.50.51--47.48.49.50
4A =48.49.50.51
A=(48.49.50.51)/4
\(\dfrac{1}{1.2.3}+\dfrac{1}{2.3.4}+...+\dfrac{1}{48.49.50}\)
Tính : P = \(\frac{1}{1.2.3}+\frac{1}{2.3.4}+........+\frac{1}{48.49.50}\)
Tính nhanh:
5) 1/2 + 1/2^2 + 1/2^3 + 1/2^4 +...+ 1/2^100
6) 1/1.2.3 + 1/2.3.4 + ... + 1/48.49.50
7) -1/3 + 1/3^2 - 1/3^3 + ... + 1/3^100 - 1/3^101
8) 1/1.2.3 + 1/2.3.4 + ... + 1/37.38.39
Giúp mình với nha.... Đang gấp ai nhanh mik k cho...
2/1.2.3 + 2/2.3.4 + 2/3.4.5 + ....... + 2/48.49.50
CẤP BÁCH...CẤP BÁCH..GIÚP VỚI
M= 2/1.2.3 + 2/2.3.4 + 2/3.4.5 + ....... + 2/48.49.50
Ai nhanh mik k cho nhea
M= 2/1.2.3 + 2/2.3.4 + 2/3.4.5 +......... + 2/48.49.50
AI NHANH MÌK K CHO
AI K MÌK MÌK K LẠI CHO NHEA
Hãy tính tổng
C = 1.2.3+ 2.3.4 + 3.4.5 +...+n(n+1) ( n+2)
Tính S=1.2.3+2.3.4+3.4.5+...+97.98.99
Tính B = 1.2.3 + 2.3.4 + ... + (n - 1)n(n + 1)
Tính C = 1.4 + 2.5 + 3.6 + ...+ n(n + 3)
Tính D = 12 + 22 + 32 + ... + n2
