Read the PDF. Ask questions without losing your place.

Open a PDF and ask about the pages you’re on — Legunt suggests questions to start with. Select a line, an equation or a figure to narrow it down. The answer stays beside the page, so it’s still there when you come back.

Open in your browser Download

Free · for Mac, Windows and Linux · your PDFs stay on your device

Legunt with a textbook open: a highlighted passage on the page and the discussion about it beside the page.

Keep the question next to the source.

No copy-pasting into a chat window. No losing the page you were on. The conversation stays where the confusion started.

Open a chapter, see what to ask
Discussions reads the two pages on screen and suggests questions to start with — on the cover, where to start. Your PDF stays exactly as it is.
Ask, or narrow it to a line
Tap a question or write your own. Select a sentence or drag around a figure to ask about just that part. Answers cite where they looked.
Come back to it later
Every discussion keeps its pages or highlight. Revise from your own questions before the exam.

Made for the hard chapters.

Point at a figure, not just words

Drag around a graph, diagram or equation — even across pages — and ask about exactly that.

Answers that show their work

Every answer says what it read and where it looked, in plain words — so you can check it against the book.

Question

Use Thompson’s method to find dy/dx for y = x³: let x grow to x + dx, expand, and drop the small quantities of the second and third order.

y + dy = (x + dx)³ = x³ + 3x² dx + 3x (dx)² + (dx)³

CoachWhich of these terms can I drop, and why?

First subtract the original y = x³ from both sides. That leaves

dy = 3x² dx + 3x(dx)² + (dx)³.

You can drop the terms 3x(dx)² and (dx)³, because they contain (dx)² and (dx)³: they are second- and third-order small quantities. When dx is very small, they are negligible compared with the first-order term 3x² dx.

So the remaining first-order change is

dy ≈ 3x² dx.

What do you get after dividing that by dx?

Smaller hintCheck my stepShow answer

Practise until it sticks

Turn any exercise into a worksheet. Teach mode nudges you one step at a time — and Agent only does the work when you ask.

Your PDFs stay yours

In the desktop app, reading, highlights and notes work offline, with no account. AI only gets what a request needs from the book you’re reading — never your other books or notes. For AI, bring your own key — Legunt AI is coming soon.

Free to read. AI your way.

See pricing →

Free$0

Reading, highlights, notes and the Playground. In the desktop app, use your own OpenAI, Anthropic or Google key — they bill you directly.

Legunt AIComing soon$7 / month

Everything in Free, with AI included — no keys to set up or manage.

Open the page that needs a little more thought.

Download Open in your browser

For Mac, Windows and Linux