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已知点O(0,0),A0(0,1),An(6,7),点A1,A2…,An-1(n∈N,n≥2)是线段A0An的n等分点,则|OA0+OA1+…+OAn−1+OAn|等于5(n+1)5(n+1).

题目详情
已知点O(0,0),A0(0,1),An(6,7),点A1,A2…,An-1(n∈N,n≥2)是线段A0An的n等分点,则|
OA0
+
OA1
+…+
OAn−1
+
OAn
|等于5(n+1)5(n+1).
▼优质解答
答案和解析
如图所示,∵点A1,A2,…,An-1(n∈N,n≥2)是线段A0An的n等分点,∴A0A1=1nA0An,A0A2=2nA0An,…,A0An−1=n−1nA0An,又OA1=OA0+A0A1,…,OAn═OA0+A0An,∴OA0+OA1+…+OAn−1+OAn=OA0+1+n2A0An=( n+1)...