- A.(-∞,0)
- B.(-∞,1)
- C.(0,+∞)
- D.(1,+∞) <img src="//img1.yqda.net/question-name/fd/88ab7d604f36265bf7dbecfefa3afd.jpg" alt="" />
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- A.x1nx+C
- B.x1nx
- C.1+1nx+C <img src="//img1.yqda.net/question-name/47/d958273d50ce16f2452c101264dddb.jpg" alt="" />
- A.1
- B.0
- C.-1
- D.不存在
- A.在(-∞,-1)内,f(x)是单调增加的
- B.在(-∞,0)内,f(x)是单调增加的
- C.f(-1)为极大值
- D.f(-1)为极小值 <img src="//img1.yqda.net/question-name/34/093edbb88e7d5dd5c7e1ef996767a8.jpg" alt="" />
- A.udu+vdv
- B.u'dv+v'du
- C.udv+vdu
- D.udv-vdu
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- A.0
- B.1
- C.无穷大
- D.不能判定
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