(1)如图,点在线段延长线上,若,,证明:.
(2)如图,点在线段上,连接并延长至点,使得,连接,若,证明:.
(3)如图,点在线段延长线上,若,,点为上一点,,连接,点在的下方且,,连接,.点为的中点,连接,点为线段上的动点,连接,将沿直线翻折得到,连接,点为的中点,连接,,当最大时,直接写出的面积.
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