learned should be understandable. Therefore,
without understanding one lesson, you cannot move on to the next, since each
lesson in mathematics is based on understanding the previous one
bright-academy.org [bright-academy.org] . If you didn’t
understand the lesson the first time, don’t be discouraged. Some people have
spent months and years to understand even one single topic. Despair and
despondency are definitely not your way. Read, study, try and try again.