MATLAB: How to use symbolic toolbox to remove a redundant variable from the equation

symbolicSymbolic Math Toolbox

Dear all,

I have two equations y1 = F1(x,a,b) and y2 = F2(x,m,n), where x is an independent variable, while a, b, m and n are constants.

Assuming y1 = y2, is there a way to use symbolic toolbox to remove x from above equations, and get m and n as functions of a and b (i.e. m = G1(a,b), n = G2(a,b)) ?

Thank you!

Rui

Best Answer

maybe if you put your functions here it will be better. However, logically you have two equations and three unknowns and it is not possible to find two unknown separate than x.

Consider you find the value of x from the first equation which will be equal to something as:

x = x(y1,a,b). if y1 == y2 => x = x(y2,a,b)

Then you put this in the second equation:

y2 = F2(x(y2,a,b),m,n)

Now you only have one equation and you want to find two values which are not possible.

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