lesson
A readable name and an address have different jobs
1 · Learn
Devices use network addresses to direct communication. Domain names give people readable names; DNS helps resolve names to address information. A web address can also specify a path to a resource on a service.
A familiar-looking name can be imitated with small changes. Name resolution tells a system where to connect; it does not by itself prove that the content is honest or appropriate.
2 · Worked example
I distinguish the site's domain from the path of a particular page. Changing the path can request a different resource without changing the domain.
3 · Your turn
Does resolving a domain name prove the site's claims are true?
Check your answer
No. Address resolution and content trustworthiness are different questions.
4 · Apply your learning
Label the parts of invented example URLs and explain the role of a name service using a paper lookup table.
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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