The correct answer is that Brian and Angela just need to break up, already.

From Thanks, Textbooks — a fantastic Tumblr of supremely weird and hilarious textbook examples and questions.

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Josh Kaufman is the author of the new book, The First 20 Hours: How to Learn Anything... Fast. I interviewed him about the art of rapid skill acquisition.

Longtime friend and Boing Boing contributor Andrea James has just completed a Kickstartered short film for children from LGBT families. I saw it this week, and was blown away by how funny and sweet it was. I know how hard she's worked on this; a true labor of love. I hope kids (and grown-ups) far and wide have a chance to experience both the art and the message. For readers in the SF Bay Area, there's a screening on Sunday June, 2013 in the Frameline LGBT film festival at San Francisco's Castro Theatre. Andrea writes in to Boing Boing with the backstory.—Xeni Jardin

Remember The Beastles, the amazing Beastie Boys/Beatles mashup? Hope you got a copy on your hard-drive because the RIAA's gone on a totally predictable jihad against a piece of delightful, noncommercial creativity.

Mark Frauenfelder at 8:59 am Fri, Jun 21, 2013

Josh Kaufman is the author of the new book, The First 20 Hours: How to Learn Anything... Fast. I interviewed him about the art of rapid skill acquisition.

Andrea James at 8:56 am Fri, Jun 21, 2013

Longtime friend and Boing Boing contributor Andrea James has just completed a Kickstartered short film for children from LGBT families. I saw it this week, and was blown away by how funny and sweet it was. I know how hard she's worked on this; a true labor of love. I hope kids (and grown-ups) far and wide have a chance to experience both the art and the message. For readers in the SF Bay Area, there's a screening on Sunday June, 2013 in the Frameline LGBT film festival at San Francisco's Castro Theatre. Andrea writes in to Boing Boing with the backstory.—Xeni Jardin

Cory Doctorow at 8:44 am Fri, Jun 21, 2013

Remember The Beastles, the amazing Beastie Boys/Beatles mashup? Hope you got a copy on your hard-drive because the RIAA's gone on a totally predictable jihad against a piece of delightful, noncommercial creativity.

My algebra book was all about trying to find its ex.

I wonder why.

I think a(t)=√(2)sin(t+pi/4) and b(t)=√(2)cos(t+pi/4). The answer to (d), of course, is Brian.

Actually, the things the student is asked to show are unprovable. If

a = c sin (q)

b = c cos(q)

then all of the conditions are met, but we know nothing about the relation between q and t. In other words, it’s one equation in two unknowns. Therefore, we can’t find the time derivatives without more information.

You missed that b’(t) = -a(t) gets added as a second premise. That’s what really ruins the relationship, romantic comedies notwithstanding.

An exercise in circular reasoning….

… Which means that they will like each other a quarter of the time for all eternity. Moreover, they can predict when the quarter of the time when they will dislike each other, and so plan for this while they are on good terms.

Looks like a better basis for a relationship than many…..

If one or both of them can find a job the requires predictable and compatible times away from home (working in a lumber camp two weeks on / one week off, that kind of thing), it could be a thing of beauty.

I didn’t actually do the math – what is the cycle length? Would the requisite job schedule in fact be incredibly weird?

Shay Guy got the math basically right, so this couple goes through an entire cycle roughly weekly.

That is one high drama couple.

(deleted by noob author. noobs can be so annoying 8)

Of course, as any moron with a PhD mathematics could see, the same mathematical equations presented here could model a predator-prey relationship.

The use of predator-prey model for a romantic relationship is decidedly odd. Do you mis-understand what a woman typically means where she says “My boyfriend eats me” ?

I think the lesson for me here is to finally forego mathematics as means in understanding one’s boyfriend/girlfriend/husband/spouse (singular/multiple) …mine and/or someone else’s…

Boing Boing is going to get sued by E-Harmony for publishing their secret algorithim

Math homework!!!

I think this math problem is a reference to a paper by Sergio Rinaldi that attempted to do a similar mathematical analysis of the unrequited love of Petrach for Laura by analyzing Petrarch’s poems. http://epubs.siam.org/doi/abs/10.1137/S003613999630592X

That analysis also results in a cyclical love dynamic (the name of my new band), though since it was unrequited the cycles were mostly Petrarch’s.

I wish they had added the source.

I guess if they told us the secret formula for Alice and Bob’s affair, they’d have to kill us.

The correct answer is, “None of your beeswax!”

As if relations were not tricky enough as it is already . . .