11.若偶函数f(x)在(-∞,0]上单调递减,a=log2$\frac{1}{3}$,b=log4$\frac{1}{5}$,c=${2^{\frac{3}{2}}}$,则f(a),f(b),f(c)满足( )
| A. | f(a)<f(b)<f(c) | B. | f(b)<f(a)<f(c) | C. | f(c)<f(a)<f(b) | D. | f(c)<f(b)<f(a) |
10.不等式x2-x+m>0在R上恒成立的一个必要不充分条件是( )
| A. | m>0 | B. | 0<m<1 | C. | m>$\frac{1}{4}$ | D. | m>1 |
9.已知x,y∈R,i为虚数单位,且(x-2)i-y=-1+i,则(1+i)x+y的值为( )
| A. | 4 | B. | 4+4i | C. | -4 | D. | 2i |
7.对于函数y=f(x),部x与y的对应关系如下表:
数列{xn}满足x1=1,且对任意n∈N*,点(xn,xn+1)都在函数y=f(x)的图象上,则x1+x2+x3+x4+…+x2017+x2018的值为( )
| x | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 |
| y | 3 | 7 | 5 | 9 | 6 | 1 | 8 | 2 | 4 |
| A. | 7560 | B. | 7564 | C. | 7550 | D. | 7554 |
6.两个相关变量满足如下关系:
根据表格已得回归方程:$\hat y$=9.4x+9.2,表中有一数据模糊不清,请推算该数据是( )
| x | 2 | 3 | 4 | 5 | 6 |
| y | 25 | ● | 50 | 56 | 64 |
| A. | 37.4 | B. | 39 | C. | 38.5 | D. | 40.5 |
5.若($\sqrt{x}$+$\frac{2}{{x}^{2}}$)n展开式中只有第六项的二项式系数最大,则展开式中的常数项是( )
0 239851 239859 239865 239869 239875 239877 239881 239887 239889 239895 239901 239905 239907 239911 239917 239919 239925 239929 239931 239935 239937 239941 239943 239945 239946 239947 239949 239950 239951 239953 239955 239959 239961 239965 239967 239971 239977 239979 239985 239989 239991 239995 240001 240007 240009 240015 240019 240021 240027 240031 240037 240045 266669
| A. | 90 | B. | 45 | C. | 120 | D. | 180 |