You’re in Calc II, and series feel like a list of magic rules.
You’ll see why each test works, so you can pick one instead of guessing.
From the Reminder Math channel · Two books, out early 2027
Math books that show you why.
We’re making math videos that take one idea apart, one symbol at a time, until it’s obvious. These two books, on series and on integrals, are made the same way: drawn, friendly, and with every step written out.
Every step written. Every idea drawn.
- Book I · Sequences & Series
- Adding Forever
- Book II · Integrals
- Infinitely Thin
- At release
- $49 each
- Founding readers
- $24.50 each
- Out
- Early 2027
01 Is this you?
From “I can follow the steps” to “I see why it works.”
You loved a video and want the whole story.
The same drawings and the same voice, with every step written out and exercises to keep.
You stopped at calculus years ago and want to go back.
Nothing assumed and nothing skipped. Each book reminds you of what it uses before it uses it.
02 How we make the videos
We take one idea apart until it’s obvious. Then we draw every piece.
Reminder Math is a new YouTube channel. Each episode takes one idea most of us were told to memorise and rebuilds it from nothing, in plain words and moving drawings. Here’s how an episode gets made, shown on our first one.
Episode 1 · Coming soonWhy eiπ + 1 = 0, one symbol at a time.Follow @remindermath
Before we write a word, we look at how the idea is usually taught and find the moment people get lost. That moment becomes the episode.
The script sounds like a friend at the table, not a lecture. Short sentences, plain words, and no symbol read aloud before it means something.
Each line gets a picture that moves with the voice. Orange names what we’re talking about, blue is the answer, and nothing sits still for long.
Every script is reviewed line by line and heard out loud before it’s animated. If a step makes you squint, we rewrite it.
The books are made the same way.
- The drawings
- Every sentence has a picture that moves.The same drawings, set step by step on the page.
- The voice
- Explained the way a friend would, out loud.The same voice, written down. Never “clearly”, never “it follows that”.
- The colours
- Orange names it. Blue is the answer.The same colour code on every page.
- Only in a book
- About twenty-five minutes for one idea.Every step written out, exercises with full solutions, and something to keep.
03 The books
Two books for the two places
most of us got lost.
Book I · Sequences & Series
Adding Forever
How can you add numbers forever and still land on one number?
From the first sequence to Taylor series, with every convergence test drawn so you can see why it works.
- Limits of sequences, from the picture up
- Every convergence test, and why it works
- Power and Taylor series that hug the curve
$24.50Founding readers, until release day · $49 at release
About this book Book II · Integrals
Infinitely Thin
What is an integral really adding up?
From thin rectangles to the fundamental theorem and every technique, so you choose a method instead of guessing.
- Area as a sum of infinitely thin slices
- The fundamental theorem, seen not memorised
- Substitution, by parts and partial fractions
$24.50Founding readers, until release day · $49 at release
About this book 04 How the books teach
First the picture. Then the words. Then the formula.
First you see it. One block, then two, then three, all the way up to n. A staircase.
Copy the staircase, turn it around, and set it on top. Now it’s a rectangle, n wide and n + 1 tall.
The rectangle holds n(n + 1) blocks, and one staircase is half of it. That’s all the formula says.
Up to a hundred, that’s 100 times 101, cut in half. 5050, without adding a single number.
Now you try. Same picture, a bigger staircase.
05 Founding readers
Join early, pay $24.50.
When pre-orders open, everyone on the list can buy each book for $24.50 instead of $49. The price holds until release day, for everyone who joined. It’s our thank-you for believing in the books early.
- NowJoin the listFree. One click to leave.
- Along the waySample pagesAs chapters are finished.
- Before releasePre-orders open$24.50 per book for the list.
- early 2027Release$49 per book from then on.
06 Questions
Good questions, plainly answered.
Who are these books for?
Students taking calculus (Calc II, AP Calculus BC, a first university course), people who learn on their own, and anyone coming back to math after a long break. If you can follow the steps but can’t see why they work, they’re written for you.
What do I need to know first?
Comfortable algebra and functions. The integrals book also uses derivatives. Whenever a book needs an older idea, it gives you a short reminder first. That’s where the name comes from.
When do they come out?
Early 2027. The list hears first. If a date moves, we’ll tell you when and why.
How much will they cost?
$49 each at release. People on the list can pre-order each book for $24.50 until release day. Sales tax or VAT may apply depending on where you live, and you’ll always see the final price before you pay.
Why a book, when the videos are free?
A video gives you the idea in one sitting. A book gives you every step, worked examples, exercises with full solutions, and something to come back to the night before an exam.
What happens to my email?
We use it to write to you about the books, and nothing else. We never sell or share it, and every email has a one-click unsubscribe.