求曲面[tex=4.857x1.357]yAyGqmPH6uVjsoklyRFjPsCn4ES71/IKAdIjF9MTDysk+Tc3QH5+wOsYsSqrGOMG[/tex]的[tex=2.857x1.0]nFfMk1gAq4fR5TwPu+p8Og==[/tex]曲率,并指出稍圆点和双曲点的区域.
举一反三
- 假定曲面上经过一个双曲点的两条渐进曲线在该点的曲率不为零. 证明:这两条曲线在该点的饶率的绝对值相等, 符号相反, 并且这两个饶率之积等于曲面在该点的[tex=2.857x1.0]nFfMk1gAq4fR5TwPu+p8Og==[/tex]曲率[tex=0.857x1.0]eMszuSG5by5UfRZVROYp5A==[/tex].
- 求下列函数的单调区间、凹凸区间、极值点、拐点和渐近线,并绘图(图略).(1) [tex=6.643x1.5]bfylM61K4fB2dxr0OSsfGnNoGCHA31PVTv+V6O1K8rw=[/tex](2)[tex=7.643x1.571]v8BogKFXW30N+HMJ7QR6DhxEDs5D0riUpoj095rhlGc=[/tex](3) [tex=3.714x2.143]X1YpNX45Pb+t3RD9Lv2Xa/npVx6iPUE04M2Y4K2k/cw=[/tex](4) [tex=5.071x3.0]4TWEbfJ+QFPbBo6PXWTsCrjc66tVrHBOTlDUBxhSpARz8/MfCO/nUo/gE3SyIffw[/tex](5)[tex=6.571x2.429]gt+k1kCw/+VFBVaKddmG6PvDvxiTdyZFXDwIPBeuGlw=[/tex](6)[tex=5.643x1.429]Hzyd6Qvm69qjRqgBIuKTx/cTmFyy56Dt2K/GC7NoCdc=[/tex](7) [tex=7.143x1.214]CwtdUElTamN1NqF0aKHeWGdaXEazoOnz3w3c67izzuE=[/tex](8)[tex=4.714x2.786]cxjZEag+Wbr67lAUIC3Slk2OV17yHgezOhFRferr5F0=[/tex].
- 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]
- 已知 [tex=20.929x1.5]d8BGP1cdKT10D0Rskg/R1nT0BqKLekI3ABEDBjWXx4IDBYFyzfNIE7MmVWqXqztEnMFizMrUYxbjITpymAjBAfX5F73CbagraBdVyxYrJBpJk70pkqzW24JtKoA6necHFEuh12Vdh281VUlt1a2fg4DeYYXtrDeRfUqR3/B2yoe513FmIjtZx8mo9Moabr/5[/tex], 求 [tex=4.857x1.357]yJi7HbctWy6+Nabxs5X5Qk3ey4Fed61cAe6Bt26pQw8+IEaAaN2IWvZ4sZrsP2tn[/tex] 。
- 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 。