等级性考试选择题1~3、填空题4~5:1.______ 2.______ 3.______ 4.______ 5.______
合格性试卷选择题1~8,填空题9~10:1.______ 2.______ 3.______ 4.______ 5.______ 6.______ 7.______ 8.______ 9.______ 10.______
设角a是第三象限角,则( )
A. sina
B. sina0
C. sina>0,cosa
D. sina>0,cosa>0
等比数列1,2,4,......前6项的和是( )
A. 31
B. 32
C. 63
D. 64