1.函数f(x)=Asin(ωx+φ)(A>0,ω>0,0<φ≤$\frac{π}{2}$)的图象如图所示,将f(x)的图象向左平移$\frac{π}{8}$个单位后得到函数g(x)的图象,则( )
A. | g(x)=$\sqrt{2}$sin(2x+$\frac{3π}{8}$) | B. | g(x)=$\sqrt{2}$cos2x | C. | g(x)=$\sqrt{2}$cos(2x+$\frac{3π}{8}$) | D. | g(x)=$\sqrt{2}$sin2x |
20.作短轴长为2b的椭圆的内接矩形,若该矩形面积的最大值的取值范围是[3b2,4b2],则椭圆离心率的取值范围是( )
0 252832 252840 252846 252850 252856 252858 252862 252868 252870 252876 252882 252886 252888 252892 252898 252900 252906 252910 252912 252916 252918 252922 252924 252926 252927 252928 252930 252931 252932 252934 252936 252940 252942 252946 252948 252952 252958 252960 252966 252970 252972 252976 252982 252988 252990 252996 253000 253002 253008 253012 253018 253026 266669
A. | [$\frac{\sqrt{3}}{2}$,1) | B. | [$\frac{\sqrt{5}}{3}$,$\frac{\sqrt{3}}{2}$] | C. | (0,$\frac{\sqrt{5}}{3}$] | D. | (0,$\frac{\sqrt{3}}{2}$] |