10.解下列不等式:
(1)log3x>2;
(2)log${\;}_{\frac{1}{2}}$(2x-$\frac{7}{8}$)<3;
(3)2x<3;
(4)($\frac{1}{3}$)x-1<2.
(1)log3x>2;
(2)log${\;}_{\frac{1}{2}}$(2x-$\frac{7}{8}$)<3;
(3)2x<3;
(4)($\frac{1}{3}$)x-1<2.
5.已知cosA+cosB=0,sinA+sinB=1,则cos(A+B)的值为( )
0 225556 225564 225570 225574 225580 225582 225586 225592 225594 225600 225606 225610 225612 225616 225622 225624 225630 225634 225636 225640 225642 225646 225648 225650 225651 225652 225654 225655 225656 225658 225660 225664 225666 225670 225672 225676 225682 225684 225690 225694 225696 225700 225706 225712 225714 225720 225724 225726 225732 225736 225742 225750 266669
| A. | 1 | B. | $\frac{1}{2}$ | C. | -1 | D. | -$\frac{1}{2}$ |