求助：关于优化题目编程

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本人这里有几个简单的优化问题，由于是初次使用MATLAB，请高手给与帮忙：第一题 题目描述：（3.43） Solve Exercise 3.24 for a column fixed at both ends. The buckling load for such a column is given as 4π2EI/l2. Use graphical method.
（3.24） For Exercise 3.23, treat outer radius Ro and inner radius Ri as design variables, and solve the design problem graphically. Impose the same constraints as in Exercise 3.23.
（3.23） For the minimum mass tubular column design problem formulated in Section 2.7,consider the following data: P = 50 kN; l = 5.0 m; modulus of elasticity,  E = 210 Gpa; allowable stress, σa = 250 MPa; mass density, ρ= 7850kg/m3.
Treating mean radius R and wall thickness t as design variables, solve the design
problem graphically imposing an additional constraint R/t ≤50. This constraint is needed to avoid local crippling of the column. Also impose the member size
constraints as 0.01 ≤ R ≤1.0 m; 5 ≤ t≤ 200 mm

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第二题
、(4.78) Maximize F(r, t) = (r - 3)2 + (t - 2)2

subject to
10 ≥ r + t

t ≥ 5

r, t ≥ 0

第三题
、（6.58) Maximize z = x1 + 4x2

subject to x1 + 2x2 ≤
5

2x1 + x2 = 4

x1 - x2 ≥ 1

x1, x2 ≥ 0

第四题
、8.27 f (x) = x12+ x22+ x32; d = (-2, -4, 2) at x = (1, 2, -1)

第五题
、（For the following problems, calculate the initial interval of uncertainty for the equal interval search with d = 0.05 at the given point and the search direction：8.36 Exercise 8.26）

8.26
f
(x) = (x1 + x2)2 + (x2 + x3)2; d = (-4, -8, -4)
at
x = (1, 1, 1)

第七题
、（）（1.7）De Jong’s Function

其中：

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