7.“%”运算使(1,3)%[2,4]=(1,2),(2,5)%(4,5)=(2,4],则{1,2,3,4,5}%{1,3,5}%{2,4,6}=( )
| A. | {1,2,3,4,5,6} | B. | ∅ | C. | {2,4} | D. | {1,3,5} |
6.下列各组函数中表示同一函数的是( )
| A. | $f(x)=x,g(x)={(\sqrt{x})^2}$ | B. | $f(x)=\left|x\right|,g(x)=\sqrt{[}3]{x^3}$ | ||
| C. | $f(x)={x^2},g(x)=\left\{\begin{array}{l}{x^2},(x>0)\\-{x^2},(x<0)\end{array}\right.$ | D. | $f(x)=\frac{{{x^2}-1}}{x-1},g(t)=t+1(t≠1)$ |
5.如果复数z=a+2i满足条件$|z|<\sqrt{5}$,那么实数a的取值范围是( )
| A. | $(-2\sqrt{2},2\sqrt{2})$ | B. | (-2,2) | C. | (-1,1) | D. | $(-\sqrt{3},\sqrt{3})$ |
2.若函数y=$\sqrt{3}{sin^2}x+sinx•cosx-\frac{{\sqrt{3}}}{2}$的图象关于直线x=φ对称,则x=φ可以为( )
| A. | $\frac{5π}{12}$ | B. | $\frac{π}{3}$ | C. | $\frac{π}{4}$ | D. | $\frac{π}{2}$ |
1.如图是棱长为1的正方体的平面展开图,则在这个正方体中,以下结论错误的是( )
0 234578 234586 234592 234596 234602 234604 234608 234614 234616 234622 234628 234632 234634 234638 234644 234646 234652 234656 234658 234662 234664 234668 234670 234672 234673 234674 234676 234677 234678 234680 234682 234686 234688 234692 234694 234698 234704 234706 234712 234716 234718 234722 234728 234734 234736 234742 234746 234748 234754 234758 234764 234772 266669
| A. | 点M到AB的距离为$\frac{{\sqrt{2}}}{2}$ | B. | AB与EF所成角是90° | ||
| C. | 三棱锥C-DNE的体积是$\frac{1}{6}$ | D. | EF与MC是异面直线 |