what is wrong with this?

im trying to use lagrange multipliers to find mins and maxs and this is the code i wrote

syms x y L; f=(x^2)*y; g=x+(y^2)-16;

T=jacobian(f,[x y])-L*jacobian(g,[x y]);

[xsoln,ysoln,Lsoln]=solve(T,g)

im getting the following error messages:

Error using sym.getEqnsVars>checkVariables (line 92)
The second argument must be a vector of symbolic variables.

Error in sym.getEqnsVars (line 62)
    checkVariables(vars);

Error in solve>getEqns (line 450)
[eqns, vars] = sym.getEqnsVars(argv{:});

Error in solve (line 225)
[eqns,vars,options] = getEqns(varargin{:});

Answer 1

[KSSV]

You have to specify for what variable in T has to be solved.

Use

[xsoln,ysoln,Lsoln]=solve(T,[L,x,y])

The above solves for L,x,y

[xsoln,ysoln]=solve(T,[x,y])

The above solves for x,y, in terms of L.

Read the documentation part.

[Walter Roberson]

If you were thinking that you were solving for g, then you cannot do that: it is only possible to solve for variables, not for expressions.