(-2,1)-|||-C.(0,1) D. (-infty ,-2) x (1,+infty )

1.函数 =2(x)^3-3(x)^2 ()-|||-A.在(0,1)内单调递减 B.在 (-infty ,0) 内单调递减-|||-C.在 (1,+infty

讨论 (x)=dfrac (1)(x) 在区间(0,1),(1,2), (2,+infty ) (0,+infty ) 上的有界性.

(B.)(0,1). (C.)(1,2). (D.)(2,+∞).2.函数$f(x)=\frac{|x|\sin(x-2)}{x(x-1)(x-2)^{2}

1、曲线 =3(x)^4-4(x)^3+1 的凸区间是 () ;-|||-(A) (-infty ,0) (B) (1,+infty ) (C) (dfrac

(2) lim _(xarrow infty )((dfrac {x+1)(x-1))}^-dfrac (x{2)}= () ;-|||-(A)1 (B) ^d

(A.)(-1,0) (B.)(0,1) (C.)(1,2) (D.)(2,3)【例38】函数$f(x)=\frac{|x|\sin(x-2)}{x(x-

(0,1) , =2s-1,则(0,1) , =2s-1,( )。A.(0,1) , =2s-1,B.(0,1) , =2s-1,C.(0,1) , =2

[题目]函数 (x)=(x)^2+4x-1 的单调增加区间是-|||-()-|||-A、 (-infty ,2)-|||-B、 (-1,1)-|||-C、 (2

20、曲线y=x^3-x^2+3x+2的上凸区间为B、(-infty,(1)/(3)) C、(-infty,3) D、((1)/(3),+infty) E

(-2,1] D. (-2,1)