Terms and Conditions

1. Who we are

linearalgebra.info (“The Math Behind the Machine”) is run by SAURABH, an individual based in Dehradun, India. “We” and “us” mean him.

2. Using the site

Units 1–13 are free for anyone to use. Units 14–20 open after purchase. To buy, you must be 18 or older, or have a parent or guardian make the purchase for you.

3. Your account

You sign in with the email address you used at checkout, using a code or link we email you; there is no password. Keep access to that email secure. One account is for one person. An account can be signed in on up to 2 devices at a time. Please don't forward your sign-in links.

4. What you get

Buying a unit gives you a personal, non-transferable right to use it for your own learning. It does not expire and includes future updates to that unit.

5. What you may not do

You may not copy, save for redistribution, resell, share, publish or otherwise pass on the paid units or their content, or try to get around the access controls. Teachers may show any unit in their own live classes; for students to use the paid units themselves, each needs their own access or a class code from us.

6. Payments

Payments are processed by Razorpay. Prices are in Indian rupees and include all taxes. We may change prices in future; a change never affects anything you have already bought.

7. Refunds

See the Cancellation & Refund Policy.

8. The content

Every unit is made with care and its numbers are checked. It is educational material provided as it is; we may improve or correct units over time, and we can't promise any particular result from using it.

9. If we ever stop

If we ever stop running the site, we will tell buyers by email at least 30 days in advance.

10. Misuse

If an account breaks these terms — for instance by sharing access — we may suspend it after contacting you.

11. Liability

As far as the law allows, our total liability to you is limited to the amount you paid us in the 12 months before the claim.

12. Privacy

How we handle your data is explained in the Privacy Policy.

13. Law and disputes

These terms are governed by the laws of India, and the courts at Dehradun, Uttarakhand, have jurisdiction. Please write to us first — most problems are solved quickly by email.

14. Changes

We will post any changes to these terms on this page with a new date, and email buyers about important changes.

15. Contact

See Contact Us.