Question

8.Find the value of 1+2+3+4+5+...+2016+2017+2016+2015+...+3+2+1. 

 

 

Answer 1

\(=2\left(1+2+...+2016\right)+2017\\ =2\cdot\dfrac{\left(2016+1\right)\left(2016-1+1\right)}{2}+2017\\ =2017\cdot2016+2017=2017^2=4068289\)

Answer 2

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