7.下列程序框图对应的函数是( )

| A. | f(x)=x | B. | f(x)=-x | C. | f(x)=|x| | D. | f(x)=-|x| |
6.若3cos($\frac{π}{2}$-θ)+cos(π+θ)=0,则cos2θ的值为( )
| A. | $\frac{4}{5}$ | B. | -$\frac{4}{5}$ | C. | $\frac{3}{5}$ | D. | -$\frac{3}{5}$ |
3.已知数列{an}为等差数列,Sn为前n项和,公差为d,若$\frac{{S}_{2017}}{2017}$-$\frac{{S}_{17}}{17}$=100,则d的值为( )
| A. | $\frac{1}{20}$ | B. | $\frac{1}{10}$ | C. | 10 | D. | 20 |
20.已知cos(α+$\frac{π}{4}}$)=$\frac{3}{5}$,$\frac{π}{2}$≤α<$\frac{3π}{2}$,则sin2α=( )
| A. | $-\frac{4}{5}$ | B. | $\frac{4}{5}$ | C. | $-\frac{7}{25}$ | D. | $\frac{7}{25}$ |
19.已知集合A={x|x2≤4,x∈R},B={x|log2x≤2,x∈Z},则A∩B=( )
0 234514 234522 234528 234532 234538 234540 234544 234550 234552 234558 234564 234568 234570 234574 234580 234582 234588 234592 234594 234598 234600 234604 234606 234608 234609 234610 234612 234613 234614 234616 234618 234622 234624 234628 234630 234634 234640 234642 234648 234652 234654 234658 234664 234670 234672 234678 234682 234684 234690 234694 234700 234708 266669
| A. | (0,2) | B. | [0,2] | C. | {0,1,2} | D. | {1,2} |