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Solve both parts and justify the conditions used. Part A: Give the real domain and range. Part B: Evaluate the function at the stated input.

Read the idea, work independently, then explain what changed.

TOPIC 01

Functions: concept and properties: mixed assessment

A mixed assessment: identify the method, justify it and revise your reasoning.

What you will be able to explain

  • Connect the chapter skills without relying on the order of the exercises.

Try it. Leave your reasoning visible.

Use one hint at a time. A correction explains what changed, not just the final answer.

01 / Standard#Your turn

Solve both parts and justify the conditions used. Part A: Give the real domain and range. Part B: Evaluate the function at the stated input.

A: f(x)=x−2B: f(x)=x2−7x+1;f(8)\begin{gathered}\text{A: }f(x)=x^{-2}\\\text{B: }f(x)=x^2-7x+1;\quad f(8)\end{gathered}
  • Use the domain, units and sampling assumptions stated in the question.
  • Use the domain, units and sampling assumptions stated in the question.
Skills and prerequisite lessons

Working and explanation

BUILD THE REASONING

Hint 1
A: Identify the exponent, its real domain and how it changes order.
Hint 2
B: Identify the input domain, rule and requested output before substituting.
Worked solution
  1. Part A reasoning

  2. Identify the exponent, its real domain and how it changes order.

  3. Calculate or simplify this relation.

    x−2=1/x2>0(x≠0)x^{-2}=1/x^2>0\quad(x\ne0)
  4. Calculate or simplify this relation.

    y>0⇒x=1/y≠0,f(x)=yy>0\Rightarrow x=1/\sqrt y\ne0,\quad f(x)=y
  5. Every positive output is attained by the displayed nonzero input; zero is excluded as both input and output.

  6. Part B reasoning

  7. Identify the input domain, rule and requested output before substituting.

  8. Calculate or simplify this relation.

    f(8)=(8)2−7(8)+1=9f(8)=(8)^2-7(8)+1=9
  9. Function evaluation is different from solving f(x)=0.

A: Domain: x≠0; range: y>0. B: The requested value is 9.

Checks and common pitfalls: Every positive output is attained by the displayed nonzero input; zero is excluded as both input and output. Function evaluation is different from solving f(x)=0.

Reasoning checklist · self / teacher assessment
  • Solve part A with its stated restrictions.
  • Solve part B using an appropriate representation.
  • Give the reasoning and check conditions in both parts.

Think first. Reveal a hint when the class is ready.

Focus on one question

Teacher preparation and assessment

Question sequence

  • Ask students to name the relevant condition before calculating.

Board plan

  • Compare valid methods and annotate their conditions.

Anticipated thinking

  • A correct final value may still hide a missing assumption.

Assessment checklist

  • Check the method, conditions, reasoning and interpretation separately.

No sign-in. Work stays in this browser. Export before clearing browser data. Written reasoning is assessed with a checklist.

Curriculum and source notes ↗