\(s=\frac{5^2}{1\cdot6}+\frac{5^2}{6\cdot11}+\frac{5^2}{11\cdot16}\)
tại sao
a,\(\frac{2}{3}\cdot\left(\frac{1}{3}+\frac{2}{5}\right)\)
b,24+25+26+.....+99+100
c,\(\frac{16\cdot17-5}{16\cdot16+11}\)
d,\(\frac{5}{80}+\frac{5}{90}+\frac{5}{150}+\frac{5}{210}+\frac{5}{270}\)
Biến đổi biểu thức sau:
\(\frac{5}{1\cdot6}=\frac{1}{?}+\frac{1}{?}\)
a) Từ đó, tính giá trị biểu thức:
\(A=\frac{1}{1\cdot6}+\frac{1}{6\cdot11}+\frac{1}{11\cdot16}+...+\frac{1}{2017\cdot2022}\)
b) Chứng minh \(B< A\)biết:
\(B=\frac{1}{6^2}+\frac{1}{11^2}+\frac{1}{16^2}+...+\frac{1}{2022^2}\)
so sánh A và B
A=\(\left(\frac{1}{80}\right)^7\)
B=\(\left(\frac{-1}{243}\right)^6\)
Ai nhanh nhất mk k nha 3 cái vì mk có 3 nick nha
a) A = \(\frac{4}{3\cdot7}+\frac{4}{7\cdot11}+\frac{4}{11\cdot5}+...+\frac{4}{107\cdot111}\)
b) B = \(\frac{6}{15\cdot18}+\frac{6}{18\cdot21}+\frac{6}{21\cdot24}+...+\frac{6}{87\cdot90}\)
c) C = \(\frac{1}{1\cdot6}+\frac{1}{6\cdot11}+\frac{1}{11\cdot16}+...+\frac{1}{51\cdot56}\)
d) D = \(\frac{1}{1\cdot2\cdot3}+\frac{1}{2\cdot3\cdot4}+\frac{1}{3\cdot4\cdot5}+...+\frac{1}{98\cdot99\cdot100}\)
Tính:
\(\left(\frac{\left(6-4\frac{1}{2}\right):0,03}{\left(3\frac{1}{20}-2,65\right).4+\frac{2}{5}}-\frac{\left(0,3-\frac{3}{20}\right).1\frac{1}{2}}{\left(1,88+2\frac{3}{25}\right).\frac{1}{80}}\right):\frac{49}{60}\)
1, tim x bết:
,\(\frac{\left(-5^4\right).\left(-15^2\right)-5^4.\left(-3^2.5\right)}{\left(-3^4\right).25^2-\left(-15^2\right).225.5}\)\(:\)\(\frac{x}{5}\)\(=\frac{-1}{6}\)
2, cho A=\(\frac{20}{30}+\frac{20}{70}+\frac{20}{126}+...+\frac{20}{798}\)
B=\(\left(\frac{41}{2}.\frac{42}{2}.\frac{43}{2}...\frac{80}{2}\right):\left(1.3.5...79\right)\)
So sánh A và B.
3, Tính nhanh.
\(\frac{0,875+\frac{1}{2}-7\%-\frac{1}{58}}{\frac{1}{25}-\frac{1}{2}-\frac{2}{7}+\frac{2}{203}}\)\(-125\%\)
HELP ME PLEASE......
so sánh:
a)\(\left(\frac{1}{80}\right)^7và\left(\frac{1}{243}\right)^6\)
b)\(\left(\frac{3}{8}\right)^5và\left(\frac{5}{243}\right)^3\)
giải chi tiết cho mk nha!!!
Bài 1: Rút gọn biểu thức
\(A=\frac{2^{10}.13+2^{10}.65}{2^8.104}\) \(B=\frac{15.3^{11}+4.27^4}{9^7}\) \(C=\left(125^3.7^5-175^5:5\right):2016^{2017}\)
Bài 2: Tìm x:
a)\(\frac{1}{1.4}+\frac{1}{4.7}+\frac{1}{7.10}+...+\frac{1}{x.\left(x+3\right)}=\frac{6}{19}\)b)\(\left|\frac{3}{13}x^2+\frac{1}{2}\right|-\frac{3}{4}=\frac{5}{6}\)