小米同学六一儿童节期间去必胜客买披萨,点了一个12英寸的披萨。一会儿服务员过来说:“12英寸披萨卖完了,给你换2个8英寸的”,如果披萨的材料和厚度都一样,请你帮小米同学算一算划不划算?(关于披萨的知识:披萨通常做成圆形,“英寸”指的是直径长度,12英寸约是30厘米,8英寸约是20厘米)
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