The Functions Book Tag

“The woman’s screams faded, and a baby’s cry took their place.”

First line in Master of Sorrows by Justin Call

Am I doing a tag again? Yes, I am. But I was tagged this time so it’s okay! Naemi @A Book Owl’s Corner thought the bookish community needed a mathematical tag so she created one and tagged me in it, probably because she knows how much I just love math *cough*. Anyway, a tag where I can talk about books and also learn something? What’s not to like? Let’s get to it.

Rules

• Thank the person who nominated you!
• Ping-back to the original creator, Naemi @ A Book Owl’s Corner, so that she can sneakily read your answers and be thrilled at how much attention math is getting within the bookish community!
• Answer all the prompts while appreciating the mathematical beauty contained in them! (You’re more than welcome to use the original graphics so that all the canva and GeoGebra work the creator put into them will be worth it…)
• Tag some people! Five would be best, since five is obviously the coolest natural number out there, but any other quantity works, too.

The constant zero function x ↦ 0 maps every number to zero. And although finding its intersections with other functions is one of mathematicians’ greatest obsessions, one can’t deny that the zero function itself just isn’t all that exciting…

For this prompt, pick a book so monotonously boring you almost fell asleep reading it!

Master of Sorrows by Justin Call. Someone needs to tell Justin Call that he doesn’t need to be obsessed with every single little thing his main character does. I didn’t need several pages about him collecting water for cooking or him putting on his clothes in the morning. The book is almost 600 pages long but only spans a couple of days if I remember correctly because we need to know about absolutely everything!

Also known as the identity map, the function x ↦ x is central to mathematics. Not only is it the most basic linear function in existence, but it also gives certain collections of functions a group structure by functioning as the group’s neutral element: When you compose a function with the identity map, you obtain the same function as before.

For this prompt, choose a book with a generic plot that you can’t help but love!

I really struggled to define “generic plot” but ended up picking Red, White and Royal Blue by Casey McQuiston. Not that I’ve read other books where a British Prince falls in love with the son of the President of the United States, but I’ve read hate-to-love romances and books whose main selling point is that they have a cute romance. And this one is really sweet!

The graphs of degree-two polynomial functions such as x ↦ x² are called parabolas. When the corresponding polynomial’s leading coefficient is positive, as is the case here, the parabola is symmetrical to a vertical line going through its lowest point, the vertex.

For this prompt, choose a book or series with an epic beginning and ending, but a lackluster middle!

To Paradise by Hanya Yanagihara feels very appropriate for this. It’s split into three parts and yeah, the middle part was lackluster and not as strong as parts one and three. I wouldn’t call it bad but it also didn’t evoke the same emotions in me as the others did, especially the first one, so the story does have a parabola-like dip.

The inverse of x ↦ x² on the non-negative reals, the function x ↦ √x assigns the square root of a given number to that number – provided the number in question is greater than or equal to zero.

For this prompt, explore your literary roots and pick a book that got you into reading!

I remember which book got me into reading very clearly and that was Harry Potter and the Chamber of Secrets by J. K. Rowling. And no, that’s not me getting the name of the first book wrong; I literally started with the second book. In my defense, I had watched the first movie and even tried reading Philosopher’s Stone but didn’t even get through chapter one because it was about Vernon and not Harry. Then I started reading book two and never stopped.

Like parabolas, hyperbolas are conic sections – graphs obtained by intersecting the surface of a cone with a plane. The standard hyperbola is given by the map x ↦ 1/x, the most basic rational function out there.

For this prompt, choose a book with a scenario so unrealistic you can’t help thinking it’s full of hyperbole and over the top!

A book that is full of unrealistic scenarios is The Gravity of Us by Phil Stamper. The main character Cal’s father suddenly becomes an astronaut overnight without training because when you’re an airline pilot you can probably pilot a spaceship too. Then there’s Cal who’s a popular social media influencer although it’s not exactly clear how he got so many followers when he’s doing very basic stuff. And he got an internship with Buzzfeed because he wants to do REAL journalism, not the gossipy kind. At Buzzfeed? The site where a quiz will tell you what kind of chair you are? Sure.

Inarguably one of the most famous functions out there, the sine function x ↦ sin(x), is particularly well known for its characteristically wavy graph.

For this prompt, pick a book that was an emotional roller coaster of ups and downs!

As this is Naemi’s tag, I had to get this book in here somehow so I’m choosing Harry Potter and the Order of the Phoenix by J. K. Rowling. Admittedly, there are mostly downs in that book but also a few ups. I’m focusing on the emotional part of the prompt because this book always makes me feel so much. I’m right there with Harry when he’s going through all that is thrown at him in this book and I feel his anger and pain but also the rare moments of optimism.

Although often treated as an afterthought to sine, the cosine function x ↦ cos(x) is meritable in its own right. For example, π, one of the most beautiful constants in the universe, is defined in higher mathematics as twice the first positive zero of the cosine function:

Using this power series, one can show that π is precisely the ratio of a circle’s circumference to its diameter. If that isn’t cool, I don’t know what is!

For this prompt, pick a book featuring pie!

(What the hell, Naemi? How am I supposed to remember if there was pie in a book??)

But I think I remember Kvothe from Kingkiller Chronicle by Patrick Rothfuss baking a pie while telling his life story? I just don’t know if it was in the first or second book so let’s just say it’s The Wise Man’s Fear. I also have a feeling Kvothe would appreciate this kind of tag.

The quotient of sine and cosine, the tangent function x ↦ tan(x) completes our main trigonometric trio.

For this prompt, pick a book that loves to go on tangents so much that it needs footnotes to do them justice!

Best prompt of the entire tag because it means I get to talk about A Choir of Lies by Alexandra Rowland. It’s the only fiction book I’ve ever read which has incorporated footnotes and I was such a fan. Once I got the hang of checking them, they added so much to the story and the character development in particular. I don’t want to reveal too much about how the footnotes are used because part of the experience is finding out for yourself. But the book might be my favorite of the year, just saying.

As a function that is its own derivative, the natural exponential function x ↦ e^x is a symbol of absolute mathematical perfection.

For this prompt, pick your favorite book of all time!

This is a mean prompt!

I have to pick two because I have a fantasy favorite and a non-fantasy favorite. It’s allowed! My fantasy favorite is The Girl in the Tower by Katherine Arden, the second book in her Winternight Trilogy, and my non-fantasy favorite is A Little Life by Hanya Yanagihara. Both books were deeply inspiring to me although in different ways.

The inverse of the natural exponential function, the natural logarithm function x ↦ ln(x), sometimes also written as x ↦ log(x), is extremely relevant to anyone studying in a scientific field. We’d have run out of paper long ago without the introduction of logarithmic scales!

For this prompt, choose a book that features logs or journal entries!

Not a book made entirely out of journal entries, but the ones that are there are pretty much just as important as this logarithmic function: The Final Empire by Brandon Sanderson. The journal entries are the epigraphs before each chapter and they make very little sense until all is revealed. Much like all this math doesn’t feel like it has been revealed to me yet.

An example of a fractal curve, the Weierstrass function x ↦ W_α(x) is continuous everywhere but differentiable nowhere. By discovering it, German mathematician Karl Weierstraß was able to disprove the previously popular claim that such functions did not exist, earning the function the moniker “monster”.

For this prompt, choose a book you find truly intimidating!

Tigana by Guy Gavriel Kay. I’m intimidated by both the book and the author and I’m honestly still not sure I’ll ever read this. It has just been presented to me as one of those fantasy books you just HAVE to read as a fantasy fan, especially if you’re into historical fantasy like I am. But then I’ve also heard several women having trouble with Kay’s books and that seems like a subtle red flag. And the book is almost 700 pages long so fully deserving of the title “monster”.

You’re not getting a graph for this one because looking at the Riemann zeta function s ↦ ζ(s) only really gets interesting over the complex numbers… And I’m afraid I haven’t figured out how to plot four dimensionally yet!

However, to say that the Riemann zeta function is interesting is almost an understatement. The Riemann Hypothesis, which claims that ζ has zeros only at the negative even integers and complex numbers with real part 1/2, is one of the biggest open conjectures in pure mathematics. Proving it would earn you both eternal glory and a million dollars’ worth of prize money and be just about the most satisfying thing ever!

For this final prompt, pick an intriguing book you hope to tackle in the future and are eyeing as your next possible read!

Not as exciting as tackling this mathematical problem obviously but The River of Silver by S. A. Chakraborty is my next read. My library has already tried to give it to me once but I had to postpone it because I was too slow about reading two other books. Now I’m finally ready to start it!

Thank you so much to Naemi for tagging me in this because that was a really fun challenge with a lot of creative prompts! What did you think of my answers? Do you know of books featuring pie? Tell me what you would have picked for some of these!