(1)塑料瓶、大纸盒既是
(2)用塑料瓶装水,既容易让阳光射入,又可以减少热量外流,起到
(3)大纸盒里面涂黑色,是为了
(4)塑料瓶的背面贴锡纸是为了
(5)大纸盒的盖用塑料薄膜,减少了
(6)瓶子周围用塑料泡沫填充,可起到
(7)装塑料瓶的盒子支起来,可以改变角度,以保持使
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