Tính C=1.3.5-3.5.7+5.7.9-7.9.11+...-97.99.101
Tính:
A= -1+2-3-4-5+6-7-8-9+...-2021+2023-2024
B=1.3.5+3.5.7+5.7.9+7.9.11+...+99.101.103
C=1.3+2.4+3.5+...+198.200
1. TÝnh B = 1.3^2 + 3.5^2 + 5.7^2 + … + 97.99^2
2 C = 1.3.5 – 3.5.7 + 5.7.9 – 7.9.11 + … - 97.99.101
A = \(\frac{2.4.6+4.6.8+6.8.10+8.10.12+...+198.200.202}{1.3.5+3.5.7+5.7.9+7.9.11+...+97.99.101}\) =?
tinh nhanh 1/3.5+1/3.5.7+1/5.7.9+...+1/99.101.103
Tính tổng:
H=1.3.5-3.5.7+5.7.9-7.9.11+...+95.97.99-97.99.101
E=1.33+3.53+5.73+...+49.513
F=1.992+2.982+3.972+...+49.512
\(x-\frac{6}{1.3.5}-\frac{6}{3.5.7}-...-\frac{6}{99.101.103}=0\)
1.3.5 - 3.5.7 + 5.7.9 - ... +97.99.101 = ?
Tính: 1.3.5+3.5.7+5.7.9+...+97.99.101