In problem-based optimization you create optimization variables, expressions in these variables that represent the objective and constraints or that represent equations, and solve the problem using solve. For the problem-based steps to take for optimization problems, see Problem-Based Optimization Workflow. For equation-solving, see Problem-Based Workflow for Solving Equations. To decide between the problem-based and solver-based approaches, see First Choose Problem-Based or Solver-Based Approach.

If you have a nonlinear function that is not composed of polynomials, rational expressions, and elementary functions such as exp, then convert the function to an optimization expression by using fcn2optimexpr. See Convert Nonlinear Function to Optimization Expression and Supported Operations for Optimization Variables and Expressions.