LEARN · EXPLAIN · REVISE

Find the sum of all coefficients of (2+x)^m.

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

TOPIC 01

Counting principles: mixed review

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

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

01 / Foundation#Your turn

m=4

Skills and prerequisite lessons

Working and explanation

BUILD THE REASONING

Hint 1

Decide whether choices are alternative cases or successive stages, then check overlap.

Hint 2

Substitute x=1.

Worked solution

Decide whether choices are alternative cases or successive stages, then check overlap.
Apply the stated relation and retain its conditions.
$(2+1)^{4}=81$
Use x=1 for the full coefficient sum, not 2^m unless both base coefficients equal one.

The requested value is 81.

Checks and common pitfalls: Use x=1 for the full coefficient sum, not 2^m unless both base coefficients equal one.

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

Teacher preparation and assessment