设[tex=17.571x4.786]3hRmRrUJOhe4GuvitGjZ3LCuDVr1Z6WdsUcr7PQPj2kTT00g4mp85UwxTH/kXkD+ybeO7aOS8kSV3tbC89m3b2Ck0miGmly0pm+FClpDPAEtqE2vOEDuzvMgjqFNlezRBP8rndfFXSHfHh6RYLrK3UhaKTHTOx2xDxivrVzX7f93vapCdLcy0/whF3VIByJbzsP7B0UYWM5rnEH0mreLbQ==[/tex]证明[tex=2.857x1.286]tj1rvgP4AHIdbrLux0kAEQ==[/tex]在点[tex=2.143x1.286]q8d9ecMZwZI3gbdeOe+7AA==[/tex]处连续且偏导数存在，但不可微分。

2022-06-19

设[tex=17.571x4.786]3hRmRrUJOhe4GuvitGjZ3LCuDVr1Z6WdsUcr7PQPj2kTT00g4mp85UwxTH/kXkD+ybeO7aOS8kSV3tbC89m3b2Ck0miGmly0pm+FClpDPAEtqE2vOEDuzvMgjqFNlezRBP8rndfFXSHfHh6RYLrK3UhaKTHTOx2xDxivrVzX7f93vapCdLcy0/whF3VIByJbzsP7B0UYWM5rnEH0mreLbQ==[/tex]证明[tex=2.857x1.286]tj1rvgP4AHIdbrLux0kAEQ==[/tex]在点[tex=2.143x1.286]q8d9ecMZwZI3gbdeOe+7AA==[/tex]处连续且偏导数存在，但不可微分。

答案：

证明  因为[tex=19.143x2.929]Bc5jhqttaSOS7WVKJFuLKSwzTNB+AFnA5rO2Wmv5Bz0kR+Kzy82k1/wAXUte9gxFCWawuMqf3MhPLAQMi4jOvCgDR3XhyNLcaw3ZB4/haG3EyvT8YElcdb47jtXFm3fZ6th9Rsj6NzJeLfJhmBetZqhMXxnJ7gD5GNwv5bzyqe7aooPx8pubBDqGXAnbtVJzOQXmzFJKXaDYQJX9GrvPnw==[/tex]，且[tex=10.143x1.786]2UKuFjD/z3ynrW9qmT3fUKxbvq2DKvfFC9tbGGVDPjyrCB2g1x/8+vq1Q0sTCoOuQuTSl1rGodwLKAM+MS2cHQ==[/tex]，所以[tex=12.857x1.786]2UKuFjD/z3ynrW9qmT3fUKxbvq2DKvfFC9tbGGVDPjzD0LHmIoRAMxRFAPtWgFRvYDXAvpmip51+vUo07TvR9Q==[/tex]，即[tex=2.857x1.286]tj1rvgP4AHIdbrLux0kAEQ==[/tex]在点[tex=2.143x1.286]q8d9ecMZwZI3gbdeOe+7AA==[/tex]处连续。因为 [tex=22.286x5.286]MkB4eyWlp+C6lGw05YhLMpsrnzvoLrpu7IsSES4Q+N6mEsMbDTe1LaYpnbZ9gsHH+AanmUPUwcxUSQD0SBH2hjuCwcX8/eHO96Tt+XEIwz/uMEw9M4+yW2FOgr388JI7P9zMQDvQFYbllB54ckiT8RimQ7T0RPWJO63HEbIlywOrVy53fzu1Jm+pwFJubM3gwbah7wr0j27ip+RjiJFvz7eATakzSg1j+rCLZaJyFRRn+fCYwMD+LZc2+U2q8XiRnPM4Q8KzfYaJoL1jpSYdpZW538a5TBHP8S2Br2eL49x4oNkp832XzkW9Kw6yBvNK7zmqIuQWkkzneykLurQh0jRJ2bXTbm6QHk/UYZ85Edc=[/tex]所以[tex=2.857x1.286]tj1rvgP4AHIdbrLux0kAEQ==[/tex]在点[tex=2.143x1.286]q8d9ecMZwZI3gbdeOe+7AA==[/tex]处的偏导数存在。因为[tex=23.0x3.0]KBzna0XUrmiXoQTuS8rfLaInYxRq33wWXtzuI5OcbFia8QD+rf+sBBJ16JbBna1X1GXGRWos+hx7iKeDx7jVzPkXMaDdpWiz0e+NCB76SD+g2seEHcVyHKWiE0avZrL+tF7/eCv1ZQlYsDGnJEI70IT5IEACr+XMe+Npw3bjo1SmkV4uBAPZ1wOcon6sserlRNlVjdQWpw6JTQ7QrZ5a9A==[/tex][p=align:center][tex=20.571x3.714]VkoGUkDgcxCUJJ9KMz+1yVNLWin05wxK93nzrzQePEqUTJN2m0U2G14F4IsvA9EBmzNhqADl2CU7MJTt7Jm61BeF52MhOGsu6tvuvWNXj2rlps1iIcoyZrP+gK/xiZKnA/WqMAC1TU5b2/S/WhR0gqSiEM3ycc4C/KGvO/9vRwZi3e7GtWO9DDo8j7hZQ8blzwBD2eBqqw5Q/9jB7yRx6+bOJvCWW0oV2kwSDULPgsoYk83GyUjykPWhPPw6r+2BC1Hg3lpnUUOh1/3XpzzAvAmPYW9DXUdABup91KMIQAMAjqmc9Fvu3Vtx2Ry5o0DX9htgT3qkD0jMKlgtyBRs12lbslcl/zaXksE7OJ02ms8=[/tex]所以[tex=2.857x1.286]tj1rvgP4AHIdbrLux0kAEQ==[/tex]在点[tex=2.143x1.286]q8d9ecMZwZI3gbdeOe+7AA==[/tex]处不可微分。

举一反三

内容

0
【单选题】Which of the following matrices does not have the same determinant of matrix B: [1, 3, 0, 2; -2, -5, 7, 4; 3, 5, 2, 1; -1, 0, -9,-5] A. [1, 3, 0, 2; -2, -5, 7, 4; 0, 0, 0, 0; -1, 0, -9, -5] B. [1, 3, 0, 2; -2, -5, 7, 4; 1, 0, 9, 5; -1, 0, -9, -5] C. [1, 3, 0, 2; -2, -5, 7, 4; 3, 5, 2, 1; -3, -5, -2, -1] D. [1, 3, 0, 2; -2, -5, 7, 4; 0, 0, 0, 1; -1, 0, -9, -5]
1
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2
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3
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4
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