Evaluate ⌊20143(2015)(2016)+201632014(2015)⌋.
Let x=2015.
Therefore we see that we have:
⌊20143(2015)(2016)+201632014(2015)⌋=⌊(x−1)3x(x+1)+(x+1)3(x−1)(x)⌋=⌊1x((x−1)3x+1+(x+1)3x−1)⌋=⌊1x((x−1)4+(x+1)4(x−1)(x+1))⌋=⌊1x(((x−1)2)2+((x+1)2)2x2−1)⌋=⌊1x(((x−1)2−(x+1)2)2+2(x−1)2(x+1)2x2−1)⌋=⌊1x(((2x)(−2))2+2(x2−1)2x2−1)⌋=⌊1x(((x−1+x+1)(x−1−x−1))2+2(x2−1)2x2−1)⌋=⌊1x(16x2+2(x2−1)2x2−1)⌋=⌊16x2x(x2−1)+2(x2−1)2x(x2−1)⌋=⌊16xx2−1+2(x2−1)x⌋=⌊16xx2−1+2x2x−2x⌋=⌊2x+16xx2−1−2x⌋=2x=2(2015)=4030
We can omit and ignore the difference of 16xx2−1−2x in our last step since when x=2015, their difference must be a decimal.
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