(1)求EF的长;
(2)过点F作直线l分别与直线AO、直线BC交于点H、G;
①根据上述语句,在图1上画出图形,并证明;
②过点G作直线GD∥AB,交x轴于点D,以圆O为圆心,OH长为半径在x轴上方作半圆(包括直径两端点),使它与GD有公共点P.如图2所示,当直线l绕点F旋转时,点P也随之运动,证明:,并通过操作、观察,直接写出BG长度的取值范围(不必说理);
(3)在(2)中,若点M(2,),探索2PO+PM的最小值.
同类型试题
y = sin x, x∈R, y∈[–1,1],周期为2π,函数图像以 x = (π/2) + kπ 为对称轴
y = arcsin x, x∈[–1,1], y∈[–π/2,π/2]
sin x = 0 ←→ arcsin x = 0
sin x = 1/2 ←→ arcsin x = π/6
sin x = √2/2 ←→ arcsin x = π/4
sin x = 1 ←→ arcsin x = π/2
y = sin x, x∈R, y∈[–1,1],周期为2π,函数图像以 x = (π/2) + kπ 为对称轴
y = arcsin x, x∈[–1,1], y∈[–π/2,π/2]
sin x = 0 ←→ arcsin x = 0
sin x = 1/2 ←→ arcsin x = π/6
sin x = √2/2 ←→ arcsin x = π/4
sin x = 1 ←→ arcsin x = π/2