1.若f(x)=1-x2sin x,则f(x)的导数是( )
A.-2xsin x-?1-x2?cos xsin2x
B.-2xsin x+?1-x2?cosxsin2x
C.-2xsin x+?1-x2?sin x
D.-2xsin x-?1-x2?sinx
2.函数f(x)=x+xln x在(1,1)处的切线方程为( )
A.2x+y-1=0 B.2x-y-1=0
C.2x+y+1=0 D.2x-y+1=0
3.设曲线y=x+1x-1在点(3,2)处的切线与直线ax+y+1=0垂直,则a等于( )
A.2 B.12
C.-12 D.-2
4.函数y=(2 019-8x)3的导数y′=( )
A.3(2 019-8x)2 B.-24x
C.-24(2 019-8x)2 D.24(2 019-8x)2
二、填空题
5.已知f(x)=ln(3x-1),则f′(1)=________.
6.若曲线y=xln x上点P处的切线平行于直线2x-y+1=0,则点P的坐标是________.
7.已知函数f(x)=f′π2sin x+cos x,则f′π4=________.