(2)如图2,已知菱形的周长为16,面积为,E为中点,若P为对角线上一动点,Q为边上一动点,计算的最小值:
(3)如图3,已知在四边形中,,,,E为边上一个动点,连接,过点D作,垂足为点F,在上截取.试问在四边形内是否存在点P,使得的面积最小?若存在,请你在图中画出点P的位罝,并求出的最小面积;若不存在,请说明理由.
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