Question

1又1/2-2又5/6+3又1/12-4又19/21—5又1/30+6又41/42-6又41/42—7又1/56+8又7

Answer 1

题目有误,应该得

=(1+1/2)-(3-1/6)+(3+1/12)-(5-1/20)+(5+1/30)-(7-1/42)+(7+1/56)-(9-1/72)+(9+1/90)

=(1-3+3-5+5-7+7-9+9)+(1/2+1/6+1/12+1/20+1/30+1/42+1/56+1/72+1/90)

=1+(1-1/10)

=19/10