Software Engineering › Key terms › Y11 Programming Fundamentals › Two's complement
Two's complement
Term Key terms bank Y11 Programming Fundamentals
Definition
A way of storing signed (positive and negative) integers in binary: write the positive number, invert every bit, then add 1 to get the negative. The left-most bit is the sign bit (1 = negative).
Example: 8-bit: +5 = 00000101; invert = 11111010; add 1 = 11111011 = -5.
Found in: syllabus.
Signed binary: invert bits and add 1.
Where it is used in the test
Syllabus area: Y11 Programming Fundamentals.
Question types it can appear in
- Multiple choice: Pick the option that matches the definition or example.
- Fill in the blanks: Find the 8-bit form of a negative number
- Short answer: Define, outline or explain it and tie it to the scenario.
No past question in this bank is linked to this term yet. It can still be tested through the question types above.
Study links
- Flashcard: Two's complement in Programming Fundamentals (Year 11) · study that set
- Memorise: Data structures
- Key terms bank entry: Two's complement
- Notes: Number systems, two's complement, characters (Year 11 content (Programming fundamentals, OOP, Mechatronics))
How to use it in an answer
A model sentence
“A way of storing signed (positive and negative) integers in binary: write the positive number, invert every bit, then add 1 to get the negative.” Then apply it: 8-bit: +5 = 00000101; invert = 11111010; add 1 = 11111011 = -5.
In a short answer, give the definition in your own words first, then tie it to the situation in the question. Do not copy the example above unless it fits the scenario.
Command words used with it
No linked question shows the command word for this term. Across the past short answer questions in this bank the words used most are: Explain, Outline, Describe, Compare, Classify, Analyse. Check the actual word in your question.
Technique for the question types
- Multiple choice: Read all four options, rule out wrong ones, pick one; no penalty for guessing so never leave blank.
- Fill in the blanks: Choose the right word from a list; use exact syllabus terms.
- Short answer: One clear point per mark, use the stimulus and course terms, and answer the command word.
Common mistakes
- Use the term exactly as the syllabus words it, then link it to the scenario in the question; the 2025 feedback repeatedly rewards using the stimulus.
- Answer the command word: outline gives main points only, explain gives a reason or cause, discuss gives both sides.
Related terms
Same group in the syllabus: Binary (base 2) · Decimal (base 10) · Hexadecimal (base 16) · Character representation (ASCII, Unicode) · Data types · Integer · Real (floating point) · Boolean · Character and string · Date and time · Array · Multi-dimensional array · Record · List