Question

斜率为2的直线被曲线y平方=2x所截得的线段长是4,求此直线方程.（速求答案,

Answer 1

=20102-20092+20082-20072+……+22-12

=(2010+2009)*(2010-2009)+(2008+2007)*(2008-2007)+……+(2+1)*(2-1)

=(2010+2009)*1+(2008+2007)*1+……+(2+1)*1

=2010+2009+2008+2007+……+2+1

=(2010+1)+(2009+2)+……+(1006+1005)

=2011*1005

=2021055