\(\left(5\times6+11-41\right)\times\left(1+2+3+\cdot\cdot\cdot+100\right)\)

\(=\left(30+11-41\right)\times\left(1+2+\cdot\cdot\cdot+100\right)\)

\(=\left(41-41\right)\times\left(1+2+\cdot\cdot\cdot+100\right)\)

\(=0\times\left(1+2+\cdot\cdot\cdot+100\right)\)

\(=0\)

\(\left(2+4+\cdot\cdot\cdot+100\right)\times\left(11\times7-78+1\right)\)

\(=\left(2+4+\cdot\cdot\cdot+100\right)\times\left(77+1-78\right)\)

\(=\left(2+4+\cdot\cdot\cdot+100\right)\times0\)

\(=0\)

\(20152015\times2016-20162016\times2015\)

\(=10001\times2015\times2016-10001\times2006\times2005\)

\(=0\)

Giải:

\(B=\left(5+10+15+...+2015\right)\times\left(20142014\times2015-20152015\times2014\right)\) 

\(B=\left(5+10+15+...+2015\right)\times\left(10001\times2014\times2015-10001\times2015\times2014\right)\)

\(B=\left(5+10+15+...+2015\right)\times0\) 

\(B=0\) 

Chúc em học tốt!

B = (5+10+15+.........+2015) x (20142014 x 2015-20152015 x 2014)

2016×20162015-2015×20162016+2017=20162017

Bằng 20162017.

tính nhanh

Tính nhanh nha

2014 x 20152015 + 2015 x 20142014

= 4.058615821 x 10¹⁰  + 4.058615821 x 10¹⁰

= 8.117231642 x 10¹⁰

 ^{hok tốt}