a cong tru loan nen ko hieu
b
A=5/1.4+5/4.7+..5/100.103
3/5.A=3/1.4+3/4.7+..+3/100.103
=1/1-1/4+1/4-1/7+...+1/100-1/103
=1-1/103=102/103
A=(5.102)/(3.103)=5.34/103
Tính :
a) A = \(\frac{5}{1.4}\) + \(\frac{29}{4.7}\) + \(\frac{71}{7.10}\) + ..... + \(\frac{10301}{100.103}\)
b) Q = \(\frac{1.3}{3.5}\) + \(\frac{2.4}{5.7}\) + \(\frac{3.5}{7.9}\) + .... + \(\frac{49.51}{99.101}\)
\(\frac{5}{1.3}+\frac{5}{3.5}+....+\frac{5}{99.101}\)
a) Tính tổng : \(S=\frac{5}{1.3}+\frac{5}{3.5}+\frac{5}{5.7}+...+\frac{5}{97.99}\)
thực hiện phép tính :
\(\frac{1}{1.3}+\frac{1}{3.5}+\frac{1}{5.7}+...+\frac{1}{99.101}\)
\(\frac{2^{10}.3^{31}+2^{40}.3^6}{2^{11}.3^{31}+2^{41}.3^6}\)
Thực hiện phép tính: \(\frac{1}{1.3}+\frac{1}{3.5}+\frac{1}{5.7}+....+\frac{1}{19.21}\)
1, Thực hiện phép tính'
\(A=\frac{155-\frac{10}{7}-\frac{5}{11}+\frac{5}{23}}{403-\frac{26}{7}-\frac{13}{11}+\frac{13}{23}}+\frac{\frac{3}{5}+\frac{3}{13}-0,9}{\frac{7}{91}+0,2-\frac{3}{10}}\)
\(B=\frac{30.4^7.3^{29}-5.14^5.2^{12}}{54.6^{14}.9^7-12.8^5.7^5}\)
Thực hiện phép tính một cách hợp lý: \(-\frac{2}{1.3}-\frac{2}{3.5}-\frac{2}{5.7}-\frac{2}{7.9}-\frac{2}{9.11}-\frac{2}{11.13}-\frac{2}{13.15}\)
thực hiện phép tính \(\frac{\frac{3}{7}-\frac{3}{11}+\frac{3}{13}}{\frac{5}{7}-\frac{5}{11}+\frac{5}{13}}+\frac{\frac{1}{2}-\frac{1}{3}+\frac{1}{4}}{\frac{5}{4}-\frac{5}{6}+\frac{5}{8}}\)
Tìm |x| biết :
a)x=\(-1\frac{1}{5}\)
b)\(x+25\frac{1}{2}=0\)
c)\(\frac{1}{1.3}+\frac{1}{3.5}+...+\frac{1}{47.49}=\frac{1}{x}\)
d)\(\frac{1}{1.4}+\frac{1}{4.7}+...+\frac{1}{97.100}=\frac{x}{2}\)
