Logic Circuits into Logic Expressions
Logic gate circuits can be expressed as a circuit diagram, or as a written logic expression (sometimes known as a logic statement).
e.g. Z = ((NOT A) AND (A OR B)) OR (A OR B)
Each exam board will have their own preference on how to write a logic expression, but the principles remain the same.
How to create a written logic expression from a logic circuit diagram
The video below takes you step by step through the process of turning a logic circuit diagram into a written logic expression.