"How could that be? I checked the calculations!" Song He turned around.
"Look here. Why did you suddenly jump to this step for no apparent reason?" Teacher Xiang said with a smile. "Were you so groggy from staying up all night solving problems that you got confused?"
"Oh, this part!" Song He smiled. "I wrote an h to represent Hessy. I used Hessy's theory here."
"Hessy?" Teacher Xiang frowned and thought for a moment. "That obscure female mathematician from Britain?"
"Yes. Let me explain this part to you." Song He pulled out a fresh sheet of scratch paper.
He went through the Hessy theory he had used in solving the problem. Besides precisely repeating the original wording of Hessy's paper, he added a heap of his own understanding, trying his best to make it simple and easy to understand.
After all, his teacher's mathematical level was now below his own. It had taken him a long time to understand the minor points in Hessy's paper back then. Without simplifying the explanation, there was no way his teacher could understand it in a short time.
The facts proved that Song He had underestimated the gap between their abilities and overestimated Xiang Xiaotong's efficiency at understanding things while working through an illness.
After finishing his explanation, he looked up and saw that her face was full of bewilderment.
"You didn't understand?" Song He asked.
"I... I don't understand." Xiang Xiaotong rubbed her temples and said awkwardly, "It seems to make sense, but I keep feeling that something is wrong. My head hurts, and I can't figure it out."
"You should have understood part of it! Hessy's theory is difficult precisely because it's so counterintuitive. When you think about it, don't rely on your quick intuition. Slow down and deduce it bit by