Let me write something which is related with the exam (since these weeks are the weeks of exam, Oh Wt..!). Well *exhaling*, it is just a fad hypothesis actually. I just want to link the Exam and the function in calculus method. Now, imagine the Cartesian coordinate system in your mind.
Hypothetically, the ‘sleep duration’ and ‘the study days’ for the people (especially students) who will face the exam, will have two kinds of math function in Cartesian coordinate. Let’s say the study days are the abscissa, the sleep duration is the ordinate and the variable ‘x=H’ is the day they will face the exam.
Someone who really prepares from the inception of his study in college or school, must have the constant linear with the gradient is equal to zero. That’s
Which C refers the duration of his sleep. 5 hours for instance.
The 2nd function is contrastive with the first one. Someone who uses “one night racing system” (kebut semalam :p).. will have the function
f(x)= (H/x), H≠0
Let’s assume x=0 is the day that very far from the exam day. So for limit x approaching to zero, his sleep duration is ∞ (means He feels in comfort zone, and thinks that exam is still too long). Yet, in the nights before examination (x → H) the ordinate of his sleep duration will be 1 hour. Means he is possible to not to sleep at that time.
To more ensure that this 2nd function is correct, for x > H the sleep duration will approach to zero means he will refresh his mind (party or gaming or do something fun) till the morning since the exam is over. Am I right ? Lol.