Biết:\(n!=1\times2\times3\times...\times n\) . Tính:\(1\times1!+2\times2!+3\times3!+4\times4!+5\times5!=\)

                  AI TRẢ LỜI ĐÚNG MK SẼ TICK ĐÓ

\(A=\frac{3}{1\times1\times2\times2}+\frac{5}{2\times2\times3\times3}+...+\frac{19}{9\times9\times10\times10}\)

Tính nhanh : \(\frac{1}{8}\div12,5\%+\left(\frac{1\times2\times3+6\times4\times2}{5\times3\times1+5\times15\times25}+\frac{1}{2}\div50\%\right)-\left(\frac{1}{16}\div6,25\%+\frac{3+2+1+2+4+6}{1+3+5+25+15+5}\right)-\frac{1}{4}\div25\%\)

\(y=\frac{1\times100+2\times99+3\times98...+99\times2+100\times1}{1\times2+2\times3+3\times4+...+99\times100+100\times101}=?\)

tính

a, \(1\times2\times3\times...\times2018-1\times2\times3\times...\times2017^2\)

b,\(1500-\left\{5^2\times2^3-11\times\left[7^2-5\times2^3+8\times\left(11^2-121\right)\right]\right\}\)

Tính

\(1\times2\times3\times.........\times9-1\times2\times3\times...........\times8-1\times2\times3\times........8^2\)

Giúp mình nhé ai nhanh nhất mình tick

Tính C=\(\frac{1}{1\times2\times3}+\frac{1}{2\times3\times4}+\frac{1}{3\times4\times5}+....+\frac{1}{n\times\left(n+1\right)\times\left(n+2\right)}\)

Bạn nào giúp mik nhớ viết cả cách giải cho mik nhé!!!!!!!!!!

Tính K + 2013, biết:

K=\(\frac{1+\left(1+2\right)+\left(1+2+3\right)+...+\left(1+2+3+...+2013\right)}{2013\times1+2012\times2+2011\times3+...+2\times2012+1\times2013}\)

Tìm K sao cho: \(K-2016=\frac{1+\left(1+2\right)+\left(1+2+3\right)+...+\left(1+2+3+...+2017\right)}{2017\times1+2016\times2+2015\times3+...+2\times2016+2017\times1}\)