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Understand the Fundamental Theorem of Calculus

Build the Fundamental Theorem of Calculus from accumulation first — feel why differentiation undoes integration before you ever see the formal statement. You'll finish by pulling a real dataset and verifying the theorem numerically with your own code.

Applied14 drops~2-week path · 5–8 min/daymath

Phase 1Accumulation Functions and the Inverse Discovery

Feel accumulation functions act like running totals

4 drops
  1. Area is a function, not a single number

    6 min

    Area is a function, not a single number

  2. The height of f tells you how fast A is growing

    7 min

    The height of f tells you how fast A is growing

  3. Try to break the pattern — it won't break

    6 min

    Try to break the pattern — it won't break

  4. Now read FTC and recognize it as something you already know

    7 min

    Now read FTC and recognize it as something you already know

Phase 2Evaluating Integrals with Both Parts of FTC

Evaluate definite integrals using FTC Part 1 and 2

5 drops
  1. Part 2 is the shortcut: find an antiderivative, subtract endpoints

    7 min

    Part 2 is the shortcut: find an antiderivative, subtract endpoints

  2. When there's an integral inside a derivative, reach for Part 1

    6 min

    When there's an integral inside a derivative, reach for Part 1

  3. When the upper limit is a function of x, the chain rule shows up

    7 min

    When the upper limit is a function of x, the chain rule shows up

  4. The problem tells you which part of FTC to use — read it right

    6 min

    The problem tells you which part of FTC to use — read it right

  5. Negative area is real — the integral knows which direction you swept

    6 min

    Negative area is real — the integral knows which direction you swept

Phase 3FTC as the Bridge Between Area, Antiderivatives, and the Chain Rule

See FTC tie area, antiderivatives, and chain rule together

4 drops
  1. Three things you thought were separate are the same theorem

    6 min

    Three things you thought were separate are the same theorem

  2. When both limits are functions of x, Leibniz handles it

    7 min

    When both limits are functions of x, Leibniz handles it

  3. Physics, probability, and economics all wear the same clothes

    7 min

    Physics, probability, and economics all wear the same clothes

  4. Riemann sums approximate the integral — and they expose what FTC is doing

    7 min

    Riemann sums approximate the integral — and they expose what FTC is doing

Phase 4Your Own FTC Verification on Real Data

Verify the theorem on a real-world dataset you pick

1 drop
  1. Pull real data, accumulate it, differentiate it, and check FTC

    25 min

    Pull real data, accumulate it, differentiate it, and check FTC

Frequently asked questions

What does the Fundamental Theorem of Calculus actually say?
This is covered in the “Understand the Fundamental Theorem of Calculus” learning path. Start with daily 5-minute micro-lessons that build from fundamentals to hands-on application.
What is the difference between FTC Part 1 and FTC Part 2?
This is covered in the “Understand the Fundamental Theorem of Calculus” learning path. Start with daily 5-minute micro-lessons that build from fundamentals to hands-on application.
Why are differentiation and integration considered inverse operations?
This is covered in the “Understand the Fundamental Theorem of Calculus” learning path. Start with daily 5-minute micro-lessons that build from fundamentals to hands-on application.
How does Leibniz's rule extend the Fundamental Theorem of Calculus?
This is covered in the “Understand the Fundamental Theorem of Calculus” learning path. Start with daily 5-minute micro-lessons that build from fundamentals to hands-on application.
How can I verify the Fundamental Theorem of Calculus numerically?
This is covered in the “Understand the Fundamental Theorem of Calculus” learning path. Start with daily 5-minute micro-lessons that build from fundamentals to hands-on application.