lesson
Separate the algorithm from its syntax
1 · Learn
The algorithm 'return the input multiplied by itself' can be expressed in different languages. Python uses def square(n): return n * n for this one-line example. JavaScript can use function square(n) { return n * n; }.
Syntax differs, but the intended input-output relationship is the same for the numeric examples here. Type conversion and edge cases can differ between languages, so do not assume all superficially similar programs behave identically.
2 · Worked example
For numeric input 4, both examples return 16. That agreement is a test case, not proof that every type of input is handled identically.
3 · Your turn
What shared numeric output should both functions return for input 0?
Check your answer
0.
4 · Apply your learning
Implement the same small numeric function in two approved environments and record equivalent and different language rules.
Adult guidance and safety
Use an approved sandbox with invented data. Never ask for real passwords, personal records or access to another person's system. These text examples need executable projects and assessed evidence in two languages; reading code alone is not practical mastery.
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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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