Suppose that x2017−2x+1=0 and x=1. Find the value of x2016+x2015+⋯+x+1.
Solution — click to reveal
We can factor x2017−2x+1=0 by writing it as x2017−1−2x+2=(x2017−1)−2(x−1)=(x−1)(x2016+x2015+⋯+x+1)−2(x−1)=(x−1)(x2016+x2015+⋯+x−1).Since x=1, we must have x2016+x2015+⋯+x−1=0, so x2016+x2015+⋯+x+1=2.