Question

我在写一个Matlab解 多元方程组，不会了！

我按照你说的，写到了这里：
function M=answer(x)
M=[(abs((-288+b/(2*a))/(4*a)+b/(2*a)*(288^2*a-288*b+c-1/(4*a))+(288-b/(2*a))*h))/(sqrt((288^2*a-288*b+c-1/(4*a))^2+(288-b/(2*a))^2))=3.5;
(abs((-3.5+b/(2*a))/(4*a)+b/(2*a)*(3.5^2*a-3.5*b+c-1/(4*a))+(3.5-b/(2*a))*h))/(sqrt((3.5^2*a-3.5*b+c-1/(4*a))^2+(3.5-b/(2*a))^2))=3.5;
(abs((288-b/(2*a))/(4*a)-b/(2*a)*(288^2*a-288*b+c-1/(4*a))+(-288+b/(2*a))*h))/(sqrt((288^2*a-288*b+c-1/(4*a))^2+(288-b/(2*a))^2))=3.5;
(abs((3.5-b/(2*a))/(4*a)-b/(2*a)*(3.5^2*a-3.5*b+c-1/(4*a))+(-3.5+b/(2*a))*h))/(sqrt((3.5^2*a-3.5*b+c-1/(4*a))^2+(3.5-b/(2*a))^2))=3.5;
3.5^2*a-3.5*b+c=0];
end
有 abch 四个未知数，5个等式。理论上应该能解开。
但是我不会了0.0
你之前回答的问题是解一个单元 x 多元我不知道后面命令行怎么输入。

Answer 1

方程太多了，4个未知数，4个方程就够了，简单地用solve函数：
[a,b,c,h]=solve('(abs((-288+b/(2*a))/(4*a)+b/(2*a)*(288^2*a-288*b+c-1/(4*a))+(288-b/(2*a))*h))/(sqrt((288^2*a-288*b+c-1/(4*a))^2+(288-b/(2*a))^2))=3.5',......
'(abs((-3.5+b/(2*a))/(4*a)+b/(2*a)*(3.5^2*a-3.5*b+c-1/(4*a))+(3.5-b/(2*a))*h))/(sqrt((3.5^2*a-3.5*b+c-1/(4*a))^2+(3.5-b/(2*a))^2))=3.5',......
'(abs((288-b/(2*a))/(4*a)-b/(2*a)*(288^2*a-288*b+c-1/(4*a))+(-288+b/(2*a))*h))/(sqrt((288^2*a-288*b+c-1/(4*a))^2+(288-b/(2*a))^2))=3.5',......
'(abs((3.5-b/(2*a))/(4*a)-b/(2*a)*(3.5^2*a-3.5*b+c-1/(4*a))+(-3.5+b/(2*a))*h))/(sqrt((3.5^2*a-3.5*b+c-1/(4*a))^2+(3.5-b/(2*a))^2))=3.5')
---------------------运行结果：
a =-3.3442770803667415258307470348963
b =23.292557394606686956426206452998
c =138.80028509969324337251061851147
h =17.02365941416547021718290540605