# Equivalent form of $A\mathbf x=\mathbf b$ for a nonlinear system?

The general form of a system of linear equation is $A\mathbf x=\mathbf b$. But what is the equivalent general form for a system of nonlinear equations?

• $\mathbf f(\mathbf x)=\mathbf 0$. – Rahul Jan 22 '18 at 18:48
• The general form of a system of equations (linear or nonlinear) is $\mathbf{f}(\mathbf{x})=\mathbf{0}$, but I am not aware of any notation which will restrict to just nonlinear equations. – user491874 Jan 22 '18 at 18:51

A system of nonlinear equations always can be written as $$A(\vec{x})=\vec{b},$$ where $A$ is a nonlinear vector operator.