A=1.2+2.(3.2)+2.(5.3)+...+2.(99.50)
A=2.(3.2+5.3+...+99.50)
A=1.2+2.(3.2)+2.(5.3)+...+2.(99.50)
A=2.(3.2+5.3+...+99.50)
Bài 1:Tính tổng
A=1.2+3.4+5.6+...+99.100
Bài 2:Tính tổng
A=1.2.3+3.4.5+5.6.7+...+98.99.100
Bài 1:Tính tổng
A=1.2+3.4+5.6+...+99.100
Bài 2:Tính tổng
A=1.2.3+3.4.5+5.6.7+...+98.99.100
1.Tính
A=\(\dfrac{1}{1.2}+\dfrac{1}{2.3}+\dfrac{1}{3.4}+.....+\dfrac{1}{99.100}\)
B=\(\dfrac{3}{5.6}+\dfrac{3}{6.7}+\dfrac{3}{7.8}+.....+\dfrac{3}{101.102}\)
C=\(\dfrac{1}{1.2.3}+\dfrac{1}{3.4.5}+\dfrac{1}{5.6.7}\)
D=\(\dfrac{2}{1.3}+\dfrac{2}{3.5}+\dfrac{2}{5.7}+\dfrac{2}{7.9}\)
A=1.2.3+3.4.5+5.6.7+...+99.100.101
B=1.2^2+2.3^2+3.4^2+4.5^2+...+99.101^2
Tính gia trị biểu thức: A=1.2+2.3+3.4+...+99.100; B=12+22+32+...+992+1002; C=1.2.3+2.3.4+3.4.5+4.5.6+5.6.7+6.7.8+7.8.9+8.9.10
Tính:
A=1.2.3+2.3.4+3.4.5+4.5.6+5.6.7+6.7.8+7.8.9+8.9.10
B=1.3.5+3.5.7+5.7.9+7.9.11+......+95.97.99
C=1.2.3+3.4.5+5.6.7+7.8.9+........+98.99.100
D=1.22+2.32+3.42+4.52+....+99.1002
tính tổng : A=1.5 + 5.9 + ....+97.101+101.105
B=1.2^2+2.3^2+3.4^2+....+99.100^2
C=1.2+3.4+5.6+7.8+...+99.100
D=1.2.3+2.3.4+...+98.99.100
Tính E = 1/1.2-1/1.2.3+1/2.3-1/2.3.4+1/3.4-1/3.4.5+...+1/99.100-1/99.100.101
Tính : a, 1.2.3 + 2.3.4 + 3.4.5 + ... + (n - 1).n.(n+1)
b, 1.2.3 + 3.4.5 + 5.6.7 + 98.99.100