The love of functions and derivatives

"you're awake?"

The morning sun shines through the window, and a few sharp birdsong startled the sleeping people.

Function slowly opened his eyes and looked at the pale walls and snow-white quilts around him. His right hand was connected to the infusion bottle through a needle, and the vein felt a burst of coolness due to the injection of liquid.

Derivative sat quietly beside the functional bed, without saying a word, his eyes were very tired, he didn't know if it was because he didn't sleep all night or because of what the delivery guy said.

"I'm not dead?" Function asked softly.

"You won't die," the derivative rolled his eyes a little stiffly, covering up the decadence in his eyes, "You will just feel the pain of death, but you won't really die. The mathematical definition of existence is eternal life."

Function's lips parted slightly, full of questions about to ask, Derivative took the first step and directly said what Function wanted to ask, "I know what you want to ask."

"You want to ask me why I am so sure, what if you were rescued by a doctor with superb medical skills?"

"I have a friend..." Derivative's expression was bitter, and his voice was very soft, as if the wind blows and disperses into the air and disappears. It's a pity that you can't see it from the angle where the function is lying. Can concentrate on listening to the voice of the derivative——

"He was pierced through the heart by a steel bar, and he was sent to the hospital for emergency treatment a day later, but he did not die."

When hearing the words "I have a friend", Function was still teasing silently in his heart. Could it be that "friend" was born out of nothing?But after hearing the words behind the derivative, Function felt that he was not in awe of life enough. If it weren't for his inconvenient speech, he might have made this joke.

A topic that is too heavy is obviously not suitable for the environment of the hospital, which is filled with the smell of disinfectant water that makes people feel suffocating.Because the eyes cannot see the derivative, the function uses the function of the ears to the extreme, and then he actually heard a little fear in the derivative's tone.

Not pity, but fear.

Why is it fear?

The function is just an illusion of excessive use of ears, and while the derivative is no longer talking, he changes the topic in time: "Then, what happened later? Did the delivery man catch it?"

"No." Derivative was silent for a few seconds, as if thinking about something, he even turned his body, as if to avoid Function's eyes, but in fact he forgot that Function was lying flat on the bed, so he shouldn't be able to see it, " When I went, he had already fled, so I immediately dialed 120 and called the police."