问题
填空题
设θ∈[0,2π],
|
答案
∵
=P1P2
-OP2
=(3-2cos θ,4-2sin θ),OP1
∴|
|2=(3-2cos θ)2+(4-2sin θ)2P1P2
=29-12cos θ-16sin θ=29-20cos(θ+α),
∴3≤|
|≤7.P1P2
故答案为3≤|
|≤7.P1P2
设θ∈[0,2π],
|
∵
=P1P2
-OP2
=(3-2cos θ,4-2sin θ),OP1
∴|
|2=(3-2cos θ)2+(4-2sin θ)2P1P2
=29-12cos θ-16sin θ=29-20cos(θ+α),
∴3≤|
|≤7.P1P2
故答案为3≤|
|≤7.P1P2