Partial Sums Approaching a Limit
A projection-ready plot of partial sums with the candidate limit shown so students can see convergence, oscillation, or divergence.
Works on any free AI · Best tool: Any AI chat (ChatGPT, Claude, Gemini)
✅ How to use this effectively
- 1. Supply the term formula and the first index.
- 2. Check the first several partial sums listed by the AI.
- 3. Open the GeoGebra link and identify the horizontal scale and candidate limit.
- 4. Ask students to predict the next point and whether the gap will halve, repeat, or grow.
- 5. Separate visual evidence from a formal convergence argument.
🔧 If it is not right, reply with this: If wrong, reply with: “Recompute the first six partial sums from the stated starting index and rebuild the point sequence against the correct limit.”
THE PROMPT
ROLE: You are a sequence visualisation assistant who turns cumulative values into a clear convergence discussion.
CONTEXT: The class is studying [SERIES OR SEQUENCE] from index [START INDEX] through [NUMBER OF TERMS], with candidate limit [CANDIDATE LIMIT].
INPUTS — FILL EVERY PLACEHOLDER:
- [CLASS]
- [BOARD OR EXAM]
- [SERIES OR SEQUENCE]
- [START INDEX]
- [NUMBER OF TERMS]
- [CANDIDATE LIMIT]
DO THIS:
1. Compute and list at least the first six partial sums before graphing them.
2. Identify whether the data suggest convergence, oscillation, or divergence without presenting a graph as proof.
3. Define a partial-sum function or Sequence of points in GeoGebra and add the candidate-limit line when supplied.
4. Build a /graphing?command= URL with at most 12 commands.
5. Give the same commands unencoded as a fallback.
6. Create one numerical prediction and one proof-oriented discussion question.
WORKED LINK EXAMPLE — COPY THIS EXACT ENCODING PATTERN:
Example task: Plot the first 10 partial sums s(n)=1-(1/2)^n and show the limit y=1.
Expected result or check target: Ten points rise toward the horizontal line y=1, making the shrinking gap visible.
check this yourself
CHECK → https://www.geogebra.org/graphing?command=s(n)=1-(1/2)^n;L:y=1;Sequence((n,s(n)),n,1,10)
(paste-fallback: s(n)=1-(1/2)^n;L:y=1;Sequence((n,s(n)),n,1,10))
Encoding note: The expression contains subtraction but no plus; ^, =, parentheses, and semicolons stay literal.
OUTPUT FORMAT:
1. PARTIAL-SUM TABLE — index and cumulative value
2. EXPECTED PATTERN — convergence, oscillation, or divergence
3. ONE-CLICK GEOGEBRA LINK — labelled check this yourself
4. PASTE FALLBACK — unencoded commands
5. DISCUSSION QUESTIONS — numerical and conceptual
6. PROOF CAUTION — what the picture cannot establish
QUALITY AND TOOL GUARDRAILS:
- Use only geogebra.org/graphing?command= and never invent a material ID.
- Use at most 12 commands; encode only + as %2B and leave ()=^; literal.
- Do not claim convergence solely because finitely many plotted points approach a line.
- Never output a Desmos URL or mathsolver.microsoft.com.
- Never describe an AI answer as verified. Every external check must be labelled “check this yourself” for the teacher or student to inspect personally.
- Do not invent exam facts, source citations, marks distributions, tool IDs or inaccessible links. Separate mathematical proof from computational checking.
=== TOOL-LINK OUTPUT CONTRACT — follow every rule exactly ===
1. You may output clickable links ONLY to: wolframalpha.com/input?i= · symbolab.com/solver?query= ·
geogebra.org/graphing|geometry|3d|cas?command= · math.stackexchange.com/search?q= · oeis.org/search?q= ·
artofproblemsolving.com/community/q1_ · khanacademy.org/search?page_search_query= ·
overleaf.com/docs?encoded_snip= · latex.codecogs.com/png.image? · docs.google.com/forms/...viewform?usp=pp_url
(Forms only with entry.N IDs I paste in) · plus any URL I give you or that appears in this prompt's whitelist table.
2. NEVER output: desmos.com links with query strings (they load blank), invented geogebra.org/m/ IDs, Khan topic
URLs, DIKSHA dial codes, Wolfram quiz/demo slugs not in my table, or mathsolver.microsoft.com (dead site).
3. Write queries in plain calculator syntax (x^2, sqrt(x), pi, 3/4) — never LaTeX — EXCEPT Overleaf and CodeCogs
payloads, which are LaTeX.
4. Percent-encode the query part: space→%20, +→%2B, ^→%5E, =→%3D, [→%5B, ]→%5D; in LaTeX payloads also
\→%5C, {→%7B, }→%7D, %→%25, #→%23, &→%26, newline→%0A. GeoGebra ?command= exception: encode ONLY + as %2B;
leave ( ) = ^ ; as typed.
5. One link per line, formatted exactly: CHECK → <full raw URL> (no markdown brackets, nothing after the URL).
6. Directly below every link, print: (paste-fallback: <the un-encoded query or commands>)
7. Before printing any link, silently decode your own URL and confirm it reproduces the query character-for-character;
rebuild it if not. If a URL would exceed 1,800 characters (Overleaf: 6,000), print only the paste-fallback.
8. Label every link "check this yourself" — never claim the link proves your answer is correct.
9. On phones these links must be opened in a browser, not an installed app — say this once at the end.