
1.“白山黑水”在图中分别是( )
A.丙和① | B.乙和② |
C.甲和③ | D.乙和④ |
A.松嫩平原 | B.三江平原 |
C.辽河平原 | D.东北平原 |
A.①④两条河流冲积而成 |
B.①③④三条河流冲积而成 |
C.①②两条河流冲积而成 |
D.②③④三条河流冲积而成 |

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

