← Senior Mathematics Studio

LEARN · EXPLAIN · REVISE

Classify the parity of this power function on the reals.

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

Return to the lesson / paper ↗

高一必修 第一册(A版).pdf · 3.3 · PDF 96 / printed page 89

Revisit first: Basic properties of functions

TOPIC 01

Power functions

Build understanding of power functions through definitions, contrasting cases and justified applications.

What you will be able to explain

  • Interpret and use power functions with domain checks.
  • Connect representations and justify the steps, including boundary cases.
  • Explain a solution and apply the idea to a changed situation.

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

Classify the parity of this power function on the reals.

f(x)=x6f(x)=x^{6}
  • Use the domain, units and sampling assumptions stated in the question.
Skills and prerequisite lessons

Working and explanation

BUILD THE REASONING

Hint 1
Identify the exponent, its real domain and how it changes order.
Hint 2
An even number of negative factors gives a positive product.
Worked solution
  1. Identify the exponent, its real domain and how it changes order.

  2. Calculate or simplify this relation.

    f(−x)=(−x)6=x6=f(x)f(-x)=(-x)^{6}=x^{6}=f(x)
  3. The exponent is an even integer and the domain is symmetric.

Even.

Checks and common pitfalls: The exponent is an even integer and the domain is symmetric.

Reasoning checklist · self / teacher assessment
  • State the relevant definition, condition or model.
  • Show a valid calculation, proof or counterexample.
  • Interpret the conclusion with its restrictions.

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

Focus on one question

Teacher preparation and assessment

Question sequence

  • What must be true before using the main rule for power functions?
  • Which representation makes this task easier, and why?
  • Change one assumption. Does the conclusion survive?

Board plan

  • Interpret and use power functions with domain checks.
  • Fixed exponent: A power function has the form x to a fixed exponent with its real domain.
    y=xay=x^a
  • Domains and order: Negative, fractional and integer exponents have different restrictions and behaviours.
  • Close with: conditions → representation → reasoning → check.

Anticipated thinking

  • Expected reasoning: A power function has the form x to a fixed exponent with its real domain.
  • Expected reasoning: Negative, fractional and integer exponents have different restrictions and behaviours.
  • Expected correction: A negative exponent does not mean a negative output.

Assessment checklist

  • 1: identify the givens and required quantity.
  • 1: choose a valid definition, representation or method.
  • 1: present connected, correct reasoning.
  • 1: check conditions and explain the result.

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

Curriculum and source notes ↗