Image uploads

If you open up Cartesian Tutor on your phone, you can use your phone's camera to take a picture of your work on paper and submit it to René for feedback. You can also upload images from your computer.

Message Regeneration

If you're not satisfied with a response, you can regenerate René's last message by clicking the regenerate button (↻) that appears on the last message in your conversation.

LaTeX and mhchem support

LaTeX is a powerful typesetting system that allows you to write complex mathematical equations. You can also write chemical equations using mhchem.

The chat window is LaTeX and mhchem enabled, which is how René can write equations, formulas, and diagrams. You can highlight and copy the equations from René's response and paste it into the chat window if you're not comfortable with LaTeX.

LaTeX is optional. If you just write your best guess at the math or chemistry equation in normal symbols (+, -, *, /, ^, sqrt(x), etc.), René will probably be able to figure out what you're trying to say.

You can use the LaTeX Playground to learn LaTeX and mhchem.

Cartesian Tutor uses the latest and strongest AI models to help you learn. As of mid-2025, current state-of-the-art models have world knowledge and understanding at the level of an average Ivy League university senior in their declared major.

This means that René can help you with a wide range of topics; for example:

• Mathematics and Statistics
• Programming and Computer Science
• Science (Physics, Chemistry, Biology, Geology, Genetics, etc.)
• Humanities (History, Economics, Political Science, etc.)
• Engineering (Electrical, Mechanical, Civil, etc.)

René's limitations are that he doesn't have the experience and knowledge of somebody who has been a working professional in any of these fields, and overall tends to be book-smart but not street-smart.

If you are confused by anything - whether it's concepts from a previous unit that you've forgotten, or unfamiliar symbols, or some unfamiliar math -- just ask, and René will help you out!

We've uploaded past USNCO contests, (multiple choice only for now for ease of grading), and are working on creating a free response interface for the USNCO National Part II and IChO contests.

We're also working on a variety of other features to enhance the practice contest experience, such as:

• A hints section that you can pop open if you're stuck on a problem.
• Time tracking for each question.
• Deep links between each contest problem and the relevant lesson.
• Reliable AI grading for Free Response questions.

René's limitations are that he doesn't have the experience and knowledge of somebody who has been a working professional in any of these fields, and overall tends to be book-smart but not street-smart.

If you are confused by anything - whether it's concepts from a previous unit that you've forgotten, or unfamiliar symbols, or some unfamiliar math -- just ask, and René will help you out!

All content here - contests, solutions, hints, images, practice problems, etc. are generated with AI assistance, with a human review step, and we take responsibility for the end result. If you think there's an error, please send an email to brian@cartesiantutor.com with the page you were on and what the mistake is, and we'll look into it.

Taking practice tests will always be free. However, all AI-powered features (AI Chat-powered lessons, AI Chat-powered interactive problem solving, free response grading, hints, etc.) are subject to a Free Tier limit. The Free tier limit resets weekly.

The Competitor Plan gives you unlimited access to AI-powered features.

Contact us at support@cartesiantutor.com if you have any questions or feedback.