Question

(5*6+11-41)*(1+2+3+..+100)

(2+4+6+...+100)*(11*7-78-1)

20152015*2016-20162016*2015

 

Answer 1

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

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

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

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

\(=0\)

Answer 2

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

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

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

\(=0\)

Answer 3

\(20152015\times2016-20162016\times2015\)

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

\(=0\)