lesson
Evaluate every input combination
1 · Learn
For two Boolean inputs A and B, there are four combinations: false/false, false/true, true/false and true/true. AND is true only when both are true; OR is true when at least one is true; NOT reverses one value.
Parentheses show how a combined expression is grouped. Do not assume two differently grouped expressions have the same truth table just because they agree on one input pair.
2 · Worked example
For A = true and B = false, A AND B is false, A OR B is true, and NOT A is false.
3 · Your turn
Evaluate NOT(A AND B) when A is true and B is false.
Check your answer
True, because A AND B is false and NOT reverses it.
4 · Apply your learning
Construct all four rows for a combined expression and compare it with a second expression using the same inputs.
Adult guidance and safety
Use an approved private interpreter, simulator or authoring tool with fictional data. Trace and predict before running. Never execute unknown downloaded code, inspect real credentials or use other people's private data. Working examples still need saved-project and assessment integration before release.
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Check a calculation · Year 5 onward
Use this only when your teacher or adult allows a calculator for the task. Show your thinking first. It does not replace mental or written arithmetic and does not mark your lesson answer.
Powers, roots and trigonometry · Year 7 onward
Use only when the task allows a calculator. Choose one operation at a time and record your working. Trigonometry here always uses degrees (DEG), not radians. Inverse sine, cosine and tangent return an angle, not a reciprocal. Keep exact fractions and π in answers when requested.
Approximate numerical results use up to 12 significant digits. Inverse sine returns −90° to 90°, inverse cosine 0° to 180°, and inverse tangent −90° to 90°; these are principal values, not every possible solution of a trigonometric equation.
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