①宁宁:1÷=(1×5)÷(×5)=1.25
②君君:1÷=1÷(4÷5)=1÷0.8=1.25
A.宁宁:商不变的性质;君君:分数和除法的关系 |
B.宁宁:乘法和除法的关系;君君:除法的意义 |
C.宁宁:商不变的性质;君君:除法的意义 |
D.宁宁:除法的意义;君君:分数和除法的关系 |
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