derive the quadratic equation through optimization in matlab

To derive the quadratic equation through optimization in MATLAB, you can use the method of least squares.

Here are the steps to follow:

  1. Define the quadratic equation as: y = ax^2 + bx + c

  2. Create a matrix A with the x-values and a column vector b with the corresponding y-values.

  3. Define a vector x with the initial guess for the coefficients [a, b, c].

  4. Use the Optimization Toolbox in MATLAB to solve the least squares optimization problem. The goal is to minimize the sum of squares of the residuals between the observed y-values and the predicted y-values.

  5. Define a function to calculate the residual using the current values of a, b, and c. This function can be used in the optimization process.

  6. Use the lsqnonlin function from the Optimization Toolbox to perform the least squares optimization. Pass the function that calculates the residual, the initial guess x, and the data A and b as arguments to the function.

  7. Extract the optimized coefficients from the solution and use them to form the quadratic equation.

Here's an example implementation in MATLAB:

main.m
% Step 1: Define the quadratic equation
y = @(x,coeff) coeff(1)*x.^2 + coeff(2)*x + coeff(3);

% Step 2: Define the data
xData = [1, 2, 3, 4];
yData = [2, 6, 13, 24];

% Step 3: Define an initial guess for the coefficients
initialCoeff = [1, 1, 1];

% Step 4-7: Perform least squares optimization
coeff = lsqnonlin(@(coeff) (y(xData, coeff) - yData), initialCoeff);

% Step 8: Display the derived quadratic equation
a = coeff(1);
b = coeff(2);
c = coeff(3);
disp('The derived quadratic equation:')
disp(['y = ', num2str(a), 'x^2 + ', num2str(b), 'x + ', num2str(c)])
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This code will output the derived quadratic equation based on the given data and optimization. Adjust the xData and yData to fit your specific problem.

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