常用人口方程[tex=8.857x2.429]kxhgtiYMOCMmH9DrmPjiGrMOEYJQXQG+SaOTid4QMz1A27r0mSOL6NUTlck2LYAi[/tex]

2022-11-02

常用人口方程[tex=8.857x2.429]kxhgtiYMOCMmH9DrmPjiGrMOEYJQXQG+SaOTid4QMz1A27r0mSOL6NUTlck2LYAi[/tex]

答案：

解: [tex=0.929x1.357]3zu+/kqv5QZh8PIh6Zs99g==[/tex]平衡态人口数 [tex=1.0x1.214]QSpWrsvLbsISAe8gQyDfNg==[/tex]有[tex=8.643x1.357]ybrTdIV2WUghN9+4DVWfcBuelLnavGVsgJ7YE8pQLr0tfFEpPVCeO8Mvk0Ph3FT5[/tex]得[tex=6.286x1.214]EPDrpLqOJ8Bh5BHRzHqHqkdISgrzVirltIaeJEPrxmw=[/tex]令[tex=4.214x1.357]HNAucFeeNq9Rqd1qnOK6YWCvu7UjyXVysnSbvsxKnLw=[/tex] 有[tex=15.929x5.5]rZM5/OPAdr7aX+kNl9iwpP26BiOENguIrAY/eUbPWrIW9TCMzBz1lnhYBRxH8LuDY9hgse9X4sZcDKPv1Ia7Y3XfDYX+62L5Rs4Z4y4BbI+8yMZDog0sIPFPm+9P7DcTHGj6EFMlunk6XTaU11vh5QIElfIs+Nhpbfd6wKE0Rq3qHijo9TLaly9v5zvEDfkMER5M1MqCV/itexeie9/Hz2M1wuULE+Ih1qpvJvSW0P8j2NyQj9CCnJ7nhwKJcpVUnUhtLS79EhItff9gcW+9qhO6gJEO5DE3Je3rekJdzCeEchfGsnoaxJMSWI8/v992yrKJAhf8xqi6e0cZ0k1XLg==[/tex]从而[tex=15.071x2.786]Trtqo1KMZ5Rkh/eyrMKW0Zmfapy6tnXZQJoQhBSQgyLsPbqJfGXhvwCkilDUipaJWlKwxf9Rm/P4/Cwe4+ePdpthCSgRtv2H2ZxxvrGPYmZpgj8ryZNtPcWWcdWmWwAQ+RzR+YHnmnquYGBnYNJ1yEbep8UOre5WSMDpejmRMHI=[/tex]当 [tex=2.286x1.214]EvTBiSU3axAaKx5ctnhh4w==[/tex] 时[tex=18.5x2.786]Trtqo1KMZ5Rkh/eyrMKW0Zmfapy6tnXZQJoQhBSQgyLsPbqJfGXhvwCkilDUipaJWlKwxf9Rm/P4/Cwe4+ePdkOi/q9055FCCC4d9JcsPzAStdwG1t2Imx1qIpF34b5gWbKe6Y56jXhqEjoQJG+EgLbie6GRHkOZKm1tFR2N+LxSinpyVrz3Z/TfFfAkrQCL0QjS0ZyaqDlOBTsza1MFqQ==[/tex]所以是不稳定平衡。当[tex=2.571x1.214]oQ9nRqhA82G1BaNB8nv95Q==[/tex] 时[tex=8.143x2.429]Trtqo1KMZ5Rkh/eyrMKW0fYwPz/TVlhx61N/y7RmqVqLH1jTnHGdxea5xrSx3uHShqVlJiOez6zZbPC2zyzSx/mgGfIHNH7Sk5ltoCMsdcI=[/tex]由 [tex=3.929x1.429]6J8mllUOg4HiNnHYoN881vDyfdX/ckTsmtk8HkAuqS4=[/tex], 所以[tex=4.5x2.429]o+pCSHzfy4qqEoyXM0rObLyqL8yFQ9lpi8b8eUC/kXnjitUHyUQ9b9fpxhgC/j6c[/tex][tex=5.071x1.357]lMFcysJ8An/5iesvvM4AV1mU3Y92RszfOlbZQxTlG3Hqr1hIhoMhc0exGQnBP5t7[/tex]所以是稳定平衡。[tex=5.643x1.357]4pp2MTXswnAr1Pec+uQYZY/pnjX/5n/zxe9YORfSp+k=[/tex]当 [tex=2.857x1.214]K04XlpJFy8e17FFI5s2a3A==[/tex] 时,[tex=4.643x2.429]+9TIclT7K7r7F7nQ+VCnyl/kCsyT8TA2Pwqi2VzNe40gedWUdHbd/8iAUqN9kpV5[/tex], 所以随着 [tex=3.143x1.357]0XRvDtTnjvOpV1rdSoFK8k/bL9ba/UsBGQ+cx1R92yXymzZSYh/TJzyxLrR4eLw/[/tex]。当 [tex=2.857x1.214]pO1f5DRy9KT5DrLQ82CF3w==[/tex]时, [tex=3.929x2.429]Yz7bwVschMggdQjSIARM4XK5wSxfDwPzoGh34xIG03Q=[/tex] 所以随着 [tex=3.143x1.357]0XRvDtTnjvOpV1rdSoFK8rciNxe8rIyU/mi4JzQAkkGerLR6m+mVBeiDrCq+E733[/tex]总之当 [tex=2.857x1.357]mas/NWzG2YgzYaRGY7056BlBXF/9uk1vgst0LUwbu5M=[/tex]时，总有随时间增长而逐渐趋于零, 所以 [tex=0.643x1.0]WUJ/JHItsc3Bqx1WYNJcrg==[/tex]将在 [tex=2.571x1.214]oQ9nRqhA82G1BaNB8nv95Q==[/tex]处稳定。

举一反三

内容

0
求以 [tex=2.357x1.214]u/hcg1/55F2pvtGMeEw9pw==[/tex] 和 [tex=3.071x1.214]5sVa6GD0b7ovTx2rohhG1G+NFmzyMDXRjuEJawew8Wg=[/tex]为特解的最低阶的常系数线性齐次方程. 解由 $y=3 x$ 为特解可知 $\lambda_{1}=0$ 至少是特征方程的二重根. 由 $y=\sin 2 x$ 为特解可知特征方程有共功特征根 $\lambda_{2,3}=\pm 2 i .$ 所以特征方程为 $(\lambda-0)^{2}(\lambda-2 i)(\lambda+2 i)=0$, 即 $\lambda^{4}+4 \lambda^{2}=0 .$所以微分方程为 $y^{(4)}+4 y^{\prime \prime}=0 .$
1
set1 = {x for x in range(10)} print(set1) 以上代码的运行结果为？ A: {0, 1, 2, 3, 4, 5, 6, 7, 8, 9} B: {0, 1, 2, 3, 4, 5, 6, 7, 8, 9,10} C: {1, 2, 3, 4, 5, 6, 7, 8, 9} D: {1, 2, 3, 4, 5, 6, 7, 8, 9,10}
2
已知管内液体质点的轴向速度v与质点所在半径r成抛物线型分布规律。当r=0时,[tex=2.857x1.214]yL4l0eju4XyPt8jUgrNg4g==[/tex];当r=R时,v=0。(1)试建立[tex=7.429x1.357]2/fEMOSH0jetOvkvnsKgC12ZHzGR5wFBaxf9tzPo9Ec=[/tex]的函数关系式;(2)如果[tex=16.143x1.357]yVfQCf3dGfsrdKkJZZp8bIAnOvEOhHd1lAPZPBMIKytU9UHmxrFeFeUc4YZFK8YL[/tex]时,试求r= 0、2、4、6mm各处的切应力。(如图1 - 11)[img=450x362]17acc5175218466.png[/img]
3
[tex=2.214x1.0]Z8GWW72u+MH/mjafnp+83A==[/tex]丙酮酸经过丙酮酸脱氢酶系和柠檬酸循环产生[tex=4.0x1.214]EPDWVFNjIR8daNoozaWRDg==[/tex],生成的[tex=3.214x1.0]1AqDCKqjaAug6buHS5Z0tQ==[/tex]、[tex=3.429x1.214]HYAn2+I9AZQLWcA3ajoPaw==[/tex]和[tex=2.143x1.0]qQANfGnLx7pE5mcaEibuNg==[/tex](或[tex=2.071x1.0]YGdeb/NAM7yg+XY6SY16Fg==[/tex])的摩尔比是( )。未知类型：{'options': ['3:2:0', '4:2:1', '4:1:1', '3:1:1', '2: 2:2'], 'type': 102}
4
输出九九乘法表。 1 2 3 4 5 6 7 8 9 --------------------------------------------------------------------- 1*1=1 2*1=2 2*2=4 3*1=3 3*2=6 3*3=9 4*1=4 4*2=8 4*3=12 4*4=16 5*1=5 5*2=10 5*3=15 5*4=20 5*5=25 6*1=6 6*2=12 6*3=18 6*4=24 6*5=30 6*6=36 7*1=7 7*2=14 7*3=21 7*4=28 7*5=35 7*6=42 7*7=49 8*1=8 8*2=16 8*3=24 8*4=32 8*5=40 8*6=48 8*7=56 8*8=64 9*1=9 9*2=18 9*3=27 9*4=36 9*5=45 9*6=54 9*7=63 9*8=72 9*9=81