Chapter Fifteen: Advanced Mathematics-Back Before the College Entrance Exam, I Became a Sensation in the Science Community(Flowing waters fill the goblet.)

Gao Ming glanced at Wu Tong again. A child who loves learning is always likable, so she couldn’t help but add, “Are you planning to compete in an academic contest? If that’s the case, you actually don’t need to buy these books. If you head straight down Renhe Avenue, you’ll reach the county library. They have these textbooks, and you can borrow them directly by getting a library card with your ID!”

These were all university-level textbooks. For students who only needed them temporarily and would receive them once they got to college, buying them wasn’t a cost-effective choice. The library offered a comprehensive collection, and borrowing was simple, making it the better option.

Wu Tong slapped her forehead—she’d completely forgotten about the library! As the cultural flagship of the county, the library’s collection was quite rich. Rare editions might be lacking, but for the general public, there were plenty of books covering all sorts of topics. Wu Tong herself often borrowed books on agriculture and machinery there. How could she have overlooked this?

She vaguely remembered a teacher mentioning that students could also use their student IDs to borrow books from the library.

Given how quickly she read, buying books really wasn’t a wise or economical decision. The money her family had was earned through her parents’ hard work; unnecessary expenses should be saved whenever possible.

Wu Tong offered her heartfelt thanks to Gao Ming. “Thank you, Auntie!” She was truly grateful to this kind woman.

“No need for thanks. Hardly anyone in the county buys these textbooks, so the store doesn’t stock them either. My child is about your age—if only they loved studying as much as you do, I’d count my blessings!” Gao Ming waved her hand dismissively, just making casual conversation.

Wu Tong left the shop, turned, and rode her bike in the opposite direction. The library was at the other end of the same avenue as her school, and in fact, it was quite close to her home. The county library wasn’t all that large—a three-story building, including staff offices and storage.

Wu Tong had been there before, but only as a tagalong with her comrade Wu, just for fun and to glance at picture books.

She wasn’t very familiar with the place, so she went straight to the front desk to consult the librarian.

There weren’t many people in the library; it was one of the rare quiet places in the county. The librarian was extremely relaxed—most visitors were regulars, well-acquainted with the layout and knowing exactly what they wanted, rarely needing any help. The librarians mainly handled book records and kept the environment tidy.

It was rare for someone to ask a question, so the librarian was quite enthusiastic. “The advanced mathematics books you want are on the third shelf in Section D. All the university math books are in that area!”

People were reading in the library, so both Wu Tong and the librarian spoke softly. Following the directions, Wu Tong found her desired textbooks in Section D.

Advanced Mathematics, Analytic Geometry, Linear Algebra… She pulled out the Advanced Mathematics volume to take a look. The content was indeed profound. Although she’d finished all her high school math, at first glance it was still rather challenging. To truly master it, she’d need to enter a deep study mode for thorough understanding.

Wu Tong picked up Analytic Geometry and Linear Algebra as well, making a total of three textbooks to check out at the desk. She had already asked—the borrowing period was half a month. Even though the shelf held plenty more math books, Wu Tong was not greedy. She would start with these three, study them thoroughly, and then swap for others later.

Since she was just beginning to learn this advanced mathematics, she gave herself extra time. Later, she would adjust her borrowing strategy based on her progress.

Leaving the library, Wu Tong couldn’t help but use the edge of a book to shield her face from the glaring sunlight.

It was September, and the lingering heat of late summer was still oppressive. Earlier, she was so energized by the errand of borrowing books that she hardly noticed. Now, coming out from the library’s cool shade, the blazing sun felt particularly harsh.

Fortunately, this was one of the oldest neighborhoods, and the large trees on either side of the road provided some welcome shade. Otherwise, it would have been hard to muster the courage to go out at all.

On the way home, Wu Tong bought herself an old-fashioned ice pop to cool off. At that moment, she craved nothing but the clean, refreshing taste. In her memory, the summer heat only grew worse each year. She resolved to diligently practice the Morning Sun Vital Energy Technique to attain that legendary state of being impervious to heat and cold.

“Tongtong, you’re back. Have you eaten yet?”

Wu Jingzhong poked his head out of the kitchen when he heard the door open. Teacher Jin Yu had just gotten home as well, having attended a meeting before finishing work that morning, and was now resting in the living room.

“Did you get too hot? Come sit down and cool off. I’ll cut you some watermelon to tide you over!” He was off work today and had made a special trip to the morning market to buy a small hanging melon, left to chill in the coolest room for a refreshing treat.

These little watermelons had thin rinds and sweet flesh—perfect for one person to finish in a sitting. Split in half and eaten with a spoon, they had always been Wu Tong’s favorite.

“Don’t stand in front of the fan—be careful not to catch a chill!” Jin Yu quickly reminded her. Wu Tong, hot from her trip, liked to stand in front of the fan, but that was the fastest way to get sick.

“I know!” Wu Tong took the watermelon her father handed her, scooped out a bite, and popped it into her mouth. Then she opened her wallet and returned the book money her parents had given her that morning to Teacher Jin.

“Didn’t have time to go to the bookstore today? Keep it—you’ll need it for books next time,” Jin Yu said, handing the money back. Spending on her child’s education was never something she begrudged.

“I was mistaken. The books I need can be borrowed from the library, and today a kind aunt at the bookstore reminded me of that. Since I found an easier way, I don’t need to spend the money.” Wu Tong, munching on watermelon, waved her hand, urging her mother to take the money back.

“I’ve already got a library card!”

Hearing this, her parents immediately understood—she must have gone to the bookstore and then to the library, which meant she’d spent all her time running around and hadn’t eaten yet. They felt sorry for her, and Wu Jingzhong hurried back to the kitchen to serve food for Wu Tong and Teacher Jin. He was in charge of meals that day.

The couple had a harmonious relationship and had always practiced a cooperative approach to household chores since their marriage—laundry, cooking, cleaning, shopping, whoever had time would handle it. Because Wu Jingzhong’s job was closer to home and his hours more regular, he’d been the main cook since Wu Tong was little and had become quite skilled.

He never shirked housework.

After dinner, Wu Tong chatted with her parents for a while before returning to her room, where she connected with the Stone of Enlightenment and entered a deep study state.

She opened the Advanced Mathematics textbook she’d borrowed, the sixth edition from Tongji University, newly published in the last couple of years. The first chapter unfolded before her eyes: Functions and Limits.