9.在四边形ABCD中,∠A=∠B=∠C,点E在边AB上,∠AED=60°,则一定有( )
A. | ∠ADE=20° | B. | ∠ADE=30° | C. | ∠ADE=$\frac{1}{3}$∠ADC | D. | ∠ADE=$\frac{1}{2}$∠ADC |
3.若偶函数f(x)在(-∞,0]上单调递减,a=f(log23),b=f(log45),c=f(2${\;}^{\frac{3}{2}}$),则a,b,c满足( )
0 252884 252892 252898 252902 252908 252910 252914 252920 252922 252928 252934 252938 252940 252944 252950 252952 252958 252962 252964 252968 252970 252974 252976 252978 252979 252980 252982 252983 252984 252986 252988 252992 252994 252998 253000 253004 253010 253012 253018 253022 253024 253028 253034 253040 253042 253048 253052 253054 253060 253064 253070 253078 266669
A. | a<b<c | B. | b<a<c | C. | c<a<b | D. | c<b<a |