18.已知命题p:?x∈R,x2>0,命题q:?α,β∈R,使tan(α+β)=tanα+tanβ,则下列命题为真命题的是( )
A. | p∧q | B. | p∨(¬q) | C. | (¬p)∧q | D. | p∧(¬q) |
12.如图所示的数阵中,每行、每列的三个数均成等比数列,如果数阵中所有数的乘积等于$\frac{1}{512}$,那么a22=( )
$(\begin{array}{l}{{a}_{11}}&{{a}_{12}}&{{a}_{13}}\\{{a}_{21}}&{{a}_{22}}&{{a}_{23}}\\{{a}_{31}}&{{a}_{32}}&{{a}_{33}}\end{array})$.
0 245965 245973 245979 245983 245989 245991 245995 246001 246003 246009 246015 246019 246021 246025 246031 246033 246039 246043 246045 246049 246051 246055 246057 246059 246060 246061 246063 246064 246065 246067 246069 246073 246075 246079 246081 246085 246091 246093 246099 246103 246105 246109 246115 246121 246123 246129 246133 246135 246141 246145 246151 246159 266669
$(\begin{array}{l}{{a}_{11}}&{{a}_{12}}&{{a}_{13}}\\{{a}_{21}}&{{a}_{22}}&{{a}_{23}}\\{{a}_{31}}&{{a}_{32}}&{{a}_{33}}\end{array})$.
A. | 2 | B. | 1 | C. | $\frac{1}{2}$ | D. | $\frac{1}{4}$ |