You are probably thinking of Ramanujan.
A teacher probably taught him much of the math that he learned. Teachers are great at teaching math to students.
The word "autodidact" is used for an entirely self-taught learned person.
The opposite of "taught" could be "learned."
12 years old he was home sick and bored so he taught himself
After a mere two years of formal education as a child, Franklin taught himself just about everything else he learned.
learned e.g we were taught by learned professors
Yes, he self-taught himself.
Clarence Ellis learned to read and write while attending school. He taught himself about computers while reading a computer manual when he was at work.
Something learned is something that someone has taught to you and you have understood.
Katherine Mitchell
On his own, by sheer determination, with the help of a lesson book and his mother's encouragement.
Yes, actually. He taught himself to swim in a creek as a kid and invented a type of swim fins.