(1)请用尺规作的角平分线,交于点(要求保留作图痕迹,不写作法,在确认答案后,请用黑色笔将作图痕迹再填涂一次);
(2)根据图形猜想四边形为平行四边形,请将下面的证明过程补充完整.
证明:∵四边形是平行四边形,
∴
∵______(两直线平行,内错角相等)
又∵平分,平分,
∴,
∴
∴______(______)(填推理的依据)
又∵四边形是平行四边形
∴
∴四边形为平行四边形(______)(填推理的依据).
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