(1)如图1,在四边形中,,点是边上一点,,,连接、.判断的形状,并说明理由.
【拓展应用】
(2)如图2,在平面直角坐标系中,已知点,点,点在第四象限内,若是等腰直角三角形,则点的坐标是 .
(3)如图3,在平面直角坐标系中,已知点,点是轴上的动点,线段绕若点按逆时针方向旋转至线段,,连接、,则的最小值是 .
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