21×11≈ 49×50≈ 53×19≈ 19×21≈
69×12≈ 19×47≈ 37×89≈ 39×47≈
59×76≈ 29×73≈ 89×45≈ 62×44≈
31×56≈ 18×86≈ 19×43≈ 31×28≈
51×77≈ 13×49≈ 41×87≈ 28×85≈
61×40≈ 30×69≈ 33×29≈ 29×53≈
29×30≈ 42×19≈ 38×62≈ 59×25≈
21×38≈ 88×20≈ 32×59≈ 83×51≈
35×19≈ 62×17≈ 29×82≈ 31×68≈

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

