MATLAB: Trying to find non-zero solution.

MATLABnon-zero solution

Hello,

I am trying to solve a determinant of 4×4 matrix and getting answer equal to zero. Can anyone help me to find the other non-zero values for this equation. (means other periodic values for this function or other way to get non-zero approximations). I 'll be very thankfull if anyone can take a look at the attached file.

Best Answer

Which solution do you wish to find?

F = matlabFunction(det(X));
fplot(F,[0 .1])

It appears there might be 2 or 3 solutions. Or perhaps 2 or 3 trillion of them. Or why stop at any finite number?

vpasolve(det(X),.06)
ans =
0.01931385561569357106926176060344
vpasolve(det(X),.07)
ans =
0.069995054245726529446727985175491

Related Solutions

MATLAB: Finding all the zeroes of a discontinuous function in a particular range

It may be version-dependent.

In R2020b (Update 1), I get:

extrema = 
13.3333
   -1.0
 
ans =
-26.666666666666666666666666670975
                                 0

Plotting the function as well as the derivative:

figure
fplot(diff(moment,1),[-2 20])
hold on
fplot(moment,[-2 20])
hold off

supports those.

MATLAB: Confused about function solve

Hello Yuquan,

When you are trying to find the root of an inequality equation using the ‘solve’ function, sometimes it is required to give assumptions for the variable to get an explicit solution.

For example, in your query, if we assume that ‘x’ is greater than zero then we can get an explicit solution.

Please find here the modified code:

syms x;
assume(x > 0);
cond1 = (x - 7) * x^2 / 2 - (4 + x)*2 >= 0;
sol = solve(cond1, x, 'ReturnConditions', true);
sol.conditions

Please refer to the below link for example on finding roots of an inequality equation.

https://www.mathworks.com/help/symbolic/solve.html#bue6mw_-1

Thank You!

Best Answer

Related Solutions

MATLAB: Finding all the zeroes of a discontinuous function in a particular range

MATLAB: Confused about function solve

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