设[tex=2.071x1.286]ppSeSenXe1UVnNGbr2NR7g==[/tex]是[tex=0.643x1.286]ZsZs11iKEvfmzDIurZth8g==[/tex]次多项式函数。 证明 :1)若 [tex=2.0x1.286]kK7MVHZcJaDHzaBVACerVA==[/tex],[tex=2.286x1.286]IPZi8qKS5UDFR6X3lDed7jLwrgHecuCZb7aJM44OaU8=[/tex],[tex=1.143x1.286]PZ3wc82RrbgX5KwVcyJcmA==[/tex], [tex=3.143x1.286]xJuo6JEe+uecVsrFwzREoA==[/tex]都是正数,则 [tex=2.071x1.286]ppSeSenXe1UVnNGbr2NR7g==[/tex]在[tex=4.357x1.286]4flf87BM3DWTVk/Miz/rSa28i4GGrxj0nq+RuFPaMAw=[/tex]无零点;2)若 [tex=2.0x1.286]kK7MVHZcJaDHzaBVACerVA==[/tex], [tex=2.286x1.286]IPZi8qKS5UDFR6X3lDed7jLwrgHecuCZb7aJM44OaU8=[/tex],[tex=1.143x1.286]PZ3wc82RrbgX5KwVcyJcmA==[/tex], [tex=3.143x1.286]xJuo6JEe+uecVsrFwzREoA==[/tex]正负号相间 , 则 [tex=2.071x1.286]ppSeSenXe1UVnNGbr2NR7g==[/tex]在[tex=4.071x1.286]GPkpTB6O4hCCD3/4lWteJ/eqmeNaPIoQa2wSfsV8DyahtLQ8SRbVSdF0KdYhUzCE[/tex]无零点。
举一反三
- 若:(1)函数 f(x)在点[tex=3.714x1.357]7VByCIzkNySq3s2l9I6f5zccNJDeV+6SQrVr3iwjgB0=[/tex]有导数,而函数g(x)在点[tex=2.286x1.0]DSJKaWfJALImFxxTg/8qhA==[/tex]没有导数;(2)函数f(x)在点[tex=3.714x1.357]7VByCIzkNySq3s2l9I6f5zccNJDeV+6SQrVr3iwjgB0=[/tex]没有导数,而函数g(x)在点[tex=2.286x1.0]DSJKaWfJALImFxxTg/8qhA==[/tex]有导数;(3)函数f(x)在点[tex=3.714x1.357]7VByCIzkNySq3s2l9I6f5zccNJDeV+6SQrVr3iwjgB0=[/tex]没有导数及函数g(x)在点[tex=2.286x1.0]DSJKaWfJALImFxxTg/8qhA==[/tex]没有导数,则函数[tex=5.643x1.357]GmtX7Vop79exGU/rpqXUYw==[/tex]在已知点[tex=2.286x1.0]DSJKaWfJALImFxxTg/8qhA==[/tex]的可微性怎样?
- 6个顶点11条边的所有非同构的连通的简单非平面图有[tex=2.143x2.429]iP+B62/T05A6ZTM0eeaWiQ==[/tex]个,其中有[tex=2.143x2.429]ndZSw3zT0QTOVLVdoUto1Q==[/tex]个含子图[tex=1.786x1.286]J+vVZa2YaMpc6mJBbqVvWw==[/tex],有[tex=2.143x2.429]lmhx48evnQMhi03NovPXig==[/tex]个含与[tex=1.214x1.214]kFXZ1uR8GjycbJx+Ts2kyQ==[/tex]同胚的子图。供选择的答案[tex=3.071x1.214]3KinXFh3SXhZ7nIe1y9KEV6aadxhhJWeEy6Dij1iObdMUZkY6ZA5J2dVVjPSuhEf[/tex]:(1) 1 ;(2) 2 ;(3) 3 ; (4) 4 ;(5) 5 ;(6) 6 ; (7) 7 ; (8) 8 。
- 判断下列命题是否为真:(1)[tex=3.643x1.357]/5abqJjwKZ1qr+6hsVFF5EBvfq3ggOFNlHMClz0h9nk=[/tex](2)[tex=2.929x1.357]rGJpyjIjJpbcoBTWxP0Jiw==[/tex](3)[tex=4.5x1.357]2wycHMoqU83MyEp17iBils58bR7YLuCTI2G9NVAdlfY=[/tex](4)[tex=5.214x1.357]CTz2gu+IIm1GgNmYMGaduCRtA41wnW4WqwRWwEhq6aA=[/tex](5)[tex=4.857x1.357]1DcE2BMMOaZhTuxR/mjgsboXxfg5ET59Dp4I/jjEDuw=[/tex](6)[tex=4.643x1.357]BSryrsQYOvTP2hTWRu6t4nAuJwlSs4L9jaq70EpB+Us=[/tex](7)若[tex=6.0x1.357]y0IZLUnBO88nR8WBZYvd7QXv5S1OMINV5cQNzPyiyAc=[/tex],则[tex=3.429x1.357]1brfPwTkVVIX4GfoMIUskA==[/tex](8)若[tex=7.643x1.357]MhLfJXZnhbXiB0x3oNtFzThV4Y1mJxe1VYr7PkJE/T6hmTD3WWp+UxbNwvUQ6DHk[/tex],则[tex=4.143x1.357]LZUA94ISo1po5HWsOVeBCjo0rMvj7uw3bGw5HiZenrI=[/tex]
- 若:(1)函数 f(x)在点[tex=0.929x1.0]cjoIbYuE/p4IqfLA8eA4ZA==[/tex]有导数,而函数g(x)在此点没有导数;(2)函数f(x)和g(x)二者在点[tex=0.929x1.0]cjoIbYuE/p4IqfLA8eA4ZA==[/tex]都没有导数,可否断定它们的和[tex=7.214x1.357]oX568MWmpJJk2c1dN8FEzQ==[/tex]在点[tex=2.286x1.0]DSJKaWfJALImFxxTg/8qhA==[/tex]没有导数?
- 若:(1)函数 f(x)在点[tex=0.929x1.0]cjoIbYuE/p4IqfLA8eA4ZA==[/tex]有导数,而函数g(x)在此点没有导数;(2)在点[tex=0.929x1.0]cjoIbYuE/p4IqfLA8eA4ZA==[/tex]函数f(xr)和g(x)二者都没有导数,可否断定他们的积[tex=6.5x1.357]/gAVQ00H2rftxTI44M7tvg==[/tex]在点[tex=2.286x1.0]DSJKaWfJALImFxxTg/8qhA==[/tex]没有导数?