∴四边形为平行四边形,则________,
∵,
∴,
又∵,
∴为等边三角形,
∴,
∴,即.
请完成证明中的两个填空.并参考小刚同学思考的方法,解决下列问题:
(2)类比运用:如图2,与相交于点,,,,,,求线段的长;
(3)联系拓展:如图3,的三条中线分别为.若的面积为8,则以的长度为三边长的三角形的面积等于______(请直接写出答案).
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