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mAtlAB求偏导数

matlab求偏导步骤如下.1、第一步,双击打开matlab.2、第二步,定义两个变量a、b,在窗口中输入代码:syms a b.3、第三步,定义一个多元函数用于求偏导数,输入代码:f=exp(a)*exp(b),即f=a^2*b^2.4、第四步,分别对a、b求解偏导

先说明一下dy/dx=dy/dz*dz/dx=dz/dx/(dz/dy),这样就可以求y对x的导数啦!syms x y z z=x+y-sqrt(x^2+y^2) diff(diff(z,y),x) //z对xy的二阶导 ans =1/(x^2+y^2)^(3/2)*y*x diff(z,x)/diff(z,y) //y对x的一阶导 ans =(1-1/(x^2+y^2)^(1/2)*x)/(1-1/(x^2+y^2)^(1/2)*y) 结果LZ在自己化简吧~

syms x yz = sin(x*y);d1 = diff(z, x);d2 = diff(d1, y);d2 = diff(d2, y) % 不加分号,输出最终结果

建立符号变量命令sym和syms调用格式:x=sym('x'), 建立符号变量x;syms x y z , 建立多个符号变量x,y,z;matlab求导命令diff调用格式:diff(函数) , 求的一阶导数;diff(函数, n) , 求的n阶导数(n是具体整数);diff(函数,变量名), 求对的偏导数;diff(函数, 变量名,n) ,求对的n阶偏导数;

syms x y z z=solve('exp(z)-x*y*z','z') zdx=diff(z,x) zdxy=diff(zdx,y) 结果:z =-lambertw(0, -1/(x*y)) zdx = lambertw(0, -1/(x*y))/(x*(lambertw(0, -1/(x*y)) + 1)) zdxy = lambertw(0, -1/(x*y))^2/(x*y*(lambertw(0, -1/(x*y)) + 1)^3) - lambertw(0, -1/(x*y))/(x*y*(lambertw(0, -1/(x*y)) + 1)^2)

clearx_num=input('x=')y_num=input('y=')f=sym('x^2+y^2');dfdx=diff(f,'x')%对f求x偏导dfdy=diff(f,'y')%对f求y偏导dfdx_num=subs(dfdx,'x',x_num);dfdx_num=subs(dfdx_num,'y',y_num)dfdy_num=subs(dfdy,'y',y_num);dfdy_num=subs(dfdy_num,'x',x_num)

syms x t; z = sin(x*t^2) ddt = diff(z, t) % 对t偏导 ddx = diff(z, x) % 对x偏导 the result is ddt = 2*t*x*cos(t^2*x) ddx = t^2*cos(t^2*x)

先用SYMS 定义你的变量,然后定义你的函数,时候使用 diff('函数式','a')对a求偏导

如何用matlab进行多元函数偏导数计算可以调用 diff 函数求导.举例说明:先定义符号 x、y 以及符号二元函数表达式 z,然后调用 diff 函数求偏导,代码如下:clc;clear;syms x yz=x^2+y^2+exp(x*y);z_x=diff(z,x,1)z_y=diff(z,y,1)z_x2=diff(z,x,2)z_y2=

Your question is very difficult indeed. So far I cannot find any helpful information available either online or textbook to help me generate a correct solution indeed. But here is my code to just get petty net result as you expect to apply in your question

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