Be Passionately In Love

But to call him a jerk, he wasn't that much of one. Just as Xu Zhi was steeling herself to go up, she heard him lightly cough beside her. Staring at the blackboard, he casually reminded her, "You can use Lagrange's theorem."

However, they were currently studying definite integrals. Lagrange's theorem had been covered two weeks ago. Judging by the notes on the multifunctional blackboard, Professor Wang was probably teaching the mean value theorem for integrals today. But Xu Zhi had missed the first half of the lecture and hadn't fully grasped the mean value theorem, so she couldn't immediately write out the solution. Following Chen Luzhou's hint, she thought about how to solve it using Lagrange's theorem.

The classroom was silent except for the sound of Xu Zhi writing on the blackboard. Professor Wang waited patiently until she finished before joking, "Well, another girl who can't forget Lagrange. But he's actually paired with Cauchy."

The Lagrange mean value theorem is a special case of Cauchy's theorem, which is why some professors jokingly refer to them as a pair. In fact, Lagrange might have even been Cauchy's teacher.

At this, the entire classroom burst into laughter, and even Chen Luzhou couldn't help but smirk. Professor Wang motioned for Xu Zhi to return to her seat and rapped the multifunctional blackboard, saying sternly, "Every year, I have students who come up and immediately try to 'pull' (apply the theorem) without thinking. When they can't 'pull it out,' they look at me with constipated expressions and say, 'Professor, I can't pull it out!' But this year, someone actually pulled it out. Indeed, this problem can be solved using Lagrange's theorem."

His serious demeanor made the joke even funnier. The classroom erupted in waves of laughter again, with students doubling over in amusement—this was the first time they realized Professor Wang had a sense of humor. Professor Wang was a renowned math professor at A University, teaching both advanced algebra and calculus. However, the calculus course for their class was relatively simple, and his expectations were low—just passing was enough. Most of the time, there wasn't much interaction in class, and he only required full attendance.

But a brilliant teacher truly shines when paired with brilliant students. Similarly, encountering a student who could flexibly apply theorems made Professor Wang more excited than usual. Whether it was the reflection or something else, his eyes behind his glasses seemed much brighter. Sipping tea from his thermos and spitting out a tea leaf, he said leisurely, "Alright, back to the topic. Let me walk you through this problem again using today's method."

The classroom instantly fell silent again. Everyone looked intently at the blackboard, frantically taking notes. Xu Zhi glanced at the guy beside her, still lounging in his chair in the same posture. His notebook was open on the desk, but aside from the answer he'd written for her earlier, it was completely blank.

Honestly, after knowing him for so long, Xu Zhi had never properly seen his handwriting. The notebook only had a few Arabic numerals and formula letters—those numbers were written with flair, but it was impossible to judge his actual handwriting. Noticing her staring at his notebook, Chen Luzhou smirked and closed it, asking with inexplicable intuition, "Want to see the handwriting of a handsome guy?"

"...Where's your shame?" Xu Zhi shot him a sidelong glance and deliberately asked, "You don’t take notes even when listening to gibberish?"

Chen Luzhou calmly met her gaze and retorted matter-of-factly, "Why take notes for gibberish?"Xu Zhi thought he was showing off a bit too much. With an expressionless face, she stared at the blackboard and said, "Did you secretly study at home? You even know about Lagrange."

Chen Luzhou was also looking at the blackboard. Both of them pretended to be more focused than the other before he lowered his voice to explain, "No, we learned Lagrange's theorem in high school. During the first class this morning, I just skimmed through the first few chapters of calculus and found it a bit simpler than I expected. But I didn’t think Professor Wang would move this fast—it’s only been a month since the semester started, and we’re already on definite integrals. Just a lucky guess. If it were a different problem, we’d both be staring blankly at each other."

It was true. Chen Luzhou had only glanced through the first few chapters during the first class. Derivatives, functions, and even Lagrange and Cauchy were still manageable. He had learned some basic calculus before, but things started getting tougher later on, which was why he had sent Xu Zhi that WeChat message. If he had gone straight to Professor Wang’s lecture today, he wouldn’t have been completely lost, but it definitely wouldn’t have been easy.

Xu Zhi, however, asked curiously, "You learned Lagrange in high school? Is City No.1 High that competitive?"

Professor Wang moved quickly. After finishing the theorem, he immediately started on the textbook examples. Chen Luzhou leaned back, one hand in his pocket, the other holding a pen as he marked the examples Professor Wang was explaining. Hearing her question, he chuckled, then put down the pen and glanced at her lazily. "No, our teacher covered it in the competition prep class—though it was for physics competitions. Actually, Lagrange is more useful in physics competitions. Remember our math teacher, Jiang Changwei? A few times when we asked if we could use calculus for certain problems, he just told us not to learn calculus too early. He said it was like—"

He paused, realizing the analogy wasn’t quite appropriate, but Jiang Changwei had indeed phrased it that way.

Xu Zhi looked at him, puzzled. Chen Luzhou coughed, looking slightly awkward, then lowered his voice and quickly mumbled the last part, trying to gloss over the words. "He said there’s no need to take virility supplements at twenty—"

Xu Zhi found Chen Luzhou’s mix of arrogance and innocence amusing. "Teacher Jiang really knows how to put things."

Chen Luzhou, unusually flustered, gave a quiet "Mm" before lowering his eyes coolly. "Anyway, that’s the gist. He’s different from other teachers. He believes high school math can be solved with high school knowledge. If you insist on using calculus to solve high school problems, it’s like using a cannon to kill a mosquito—only people who lack skill would do that. Skilled people can stir-fry a big pot of food with just a spoon. That’s his philosophy. He always wanted us to solve big problems with small methods, not the other way around. So we only touched on it a few times during physics competitions." He sighed and smiled. "Next time, let’s sit separately. If we keep chatting like this, we’ll both fail this year."

The truth was, he couldn’t focus at all. Before she arrived, he could still follow a few examples, but now he couldn’t understand a single problem. Fortunately, Professor Wang rarely called on students to answer questions.

Just then, Professor Wang asked from the podium, "Alright, after all that, what’s the answer to this question?"

Classmates: "B."

Xu Zhi: "A."Professor Wang declared emphatically, "Yes, this female student is very quick to react. Choose A—it's the Newton-Leibniz formula we just discussed—"

Chen Luzhou: "..."

Still so adept at multitasking, huh?

For the latter half of the class, Xu Zhi focused intently on taking notes while Chen Luzhou stared at the blackboard, his Adam's apple bobbing slightly. Suddenly, he asked, "Are you free this weekend?"

Professor Wang currently had his back to them, writing on the board. Behind him, rows of heads were bent over, scribbling furiously. Xu Zhi was also writing with her head down, occasionally glancing up at the blackboard without so much as a sideways look in his direction. "What for?" she replied.

"I want to tutor you in math," he shamelessly said.

Xu Zhi, half her head resting on the desk, burst into laughter and looked up at him. "Chen Luzhou, have you ever watched a certain TV drama? The way you're talking right now totally matches its vibe."

"Which one? Do tell," he drawled lazily.

"'Ming Lou, kneel down. Your elder sister has a favor to ask of you.' From The Disguiser , right? I suggest you watch it. You just had that exact energy."

He chuckled. "Fine. You just want to see me struggle in class every day, don't you?"

Xu Zhi remained unfazed. "If I called Zhu Yangqi right now and he found out about your situation, do you think he’d rush over from Fengtai in the middle of the night just to witness it?"

Chen Luzhou leaned back in his chair and stayed silent. Xu Zhi glanced at him after a long pause, only to hear him muse thoughtfully, "...You just reminded me. Maybe we should invite him to dinner this weekend. Don’t tell him I’m here yet."

"I have a department gathering this weekend," Xu Zhi abruptly dropped the bombshell.

Chen Luzhou gave an indifferent "Oh," flipped his textbook back to the section on derivative functions, and decided to start over from the beginning—effectively tuning out the lecture. "Fine," he replied coolly.

During the ten-minute break, Professor Wang stepped out for a smoke, as did a few other male students. Xu Zhi and Chen Luzhou sat in the front row. When Zhao Tianqi left, he even detoured from the back to call out to Chen Luzhou, asking if he wanted to join them for a smoke.

Xu Zhi instinctively glanced at Chen Luzhou, who—unbeknownst to her—had already popped a candy into his mouth. Chewing slowly, he put on an act and said, "Can't. My lungs aren’t in great shape."

Didn’t seem like your lungs were struggling when we were kissing. Chen Luzhou had a knack for handling relationships. If he had simply said, "I don’t smoke," some might’ve thought he was putting on airs. But his brilliance lay in his ability to get along with anyone—humans or ghosts—each with their own approach.

Zhao Tianqi nodded but didn’t leave immediately. Hesitating, he glanced at Xu Zhi and then struck up a conversation. "What happened with Liu Yisi earlier?"

Truth be told, despite his long-standing ambiguous relationship with Liu Yisi, Xu Zhi had never formally met or spoken to Zhao Tianqi. She’d only heard his name. If he hadn’t initiated the conversation, she wouldn’t have recognized him as her roommate’s ambiguous love interest even if they’d crossed paths on the street.

So when Zhao Tianqi spoke, Xu Zhi didn’t immediately realize he was addressing her—she thought he was talking to Chen Luzhou. It took her a moment to process that the question was directed at her. But she didn’t have much goodwill toward him and replied coldly, "Nothing."Zhao Tianqi's eyes darted between the two of them as if he wanted to ask something. But since neither was particularly close to him, they obviously wouldn't tell him anything. He wisely took his leave. As soon as he was gone, Xu Zhi turned to Chen Luzhou and said, "Guess what he wanted to ask just now."

Chen Luzhou replied, "No need to guess. He'll ask me when we get back to the dorm. And I bet your two roommates won't stay idle either."

But Chen Luzhou underestimated people's curiosity. There was no need to wait until returning to the dorm—while Xu Zhi was still eating in the cafeteria, Xu Gongzhu and Liu Yisi had already subjected her to a thorough interrogation.

Xu Zhi took a careless bite of her lion's head meatball and said nonchalantly, "I was running late, and his seat happened to be by the door, so I just sat there."

"You didn't notice, but several girls in the back row were staring at you the whole time," Xu Gongzhu said as she poked open a milk carton. "But Chen Luzhou is also from S Province, right? Did you two know each other before?"

Xu Zhi looked surprised. "You've already found out his name that quickly? Yeah, we know each other. He was the heartthrob of our city's No.1 High School."

"Probably still is now. I heard some girls are already calling him 'Luzhou the Heartthrob.' No idea who came up with that nickname," Xu Gongzhu continued. "No wonder though—you two were chatting happily for half the class."

Liu Yisi chimed in, "Xu Zhi, do you think Chen Luzhou might like you?"

Xu Zhi sighed. "Probably a little."

Xu Gongzhu sighed along with her. "Xu Zhi, if I had even half your confidence, I wouldn't still be single."

Author's note: 200 red envelopes.

Calculus is way beyond me. I spent the whole afternoon studying it just to write this chapter, so updates might be shorter today. Will try for more tomorrow.