A normal school curriculum back then did not go so far as to teach calculus. When Einstein taught himself vector calculus, he used the textbook written by the g

A normal school curriculum back then did not go so far as to teach calculus. When Einstein taught himself vector calculus, he used the textbook written by the guy who invented it because it was the only textbook. Then he personally wrote to the guy to clear up his misconceptions. Today, you can learn this material in open university courses, and if you have a question, consult a plethora of freely available resources on the internet. Accessibility of information matters.