Well, what if he were sent back to Ancient Greece (and magically acquired the ability to speak Greek)? Even if he got all the math perfectly right, who would care? Or even understand it?

He would then spend the rest of his life ensuring that it is preserved. If necessary he would go around hunting for obscure caves with a chisel in hand. Depending, of course, on how much he cares about influencing the future of the universe as opposed to other less abstract goals.