Love triangle How trigonometry shapes the world

"We all rely on triangles to keep our modern world ticking along," according to this disappointing paean. Parker (Humble Pi), a comedian and former math teacher who runs the Stand-up Maths YouTube channel, notes that video game graphics are composed of countless tiny triangles because they can be computed more quickly than other shapes and that civil engineers favor triangular support structures because they're reliably rigid ("Three side-lengths can only form one triangle," whereas rectangles can transform into any number of parallelograms if their sides shift). Parker sometimes strays from his subject, as when he devotes a lengthy passage to chronicling the decades-long hunt for "a polygon which could perfectly cover a surface but in a way which never repeats" on the slim premise that he thinks the solution, a 13-sided shape discovered in 2023, bears a vague resemblance to an equilateral triangle. Other discussions get mired in mathematical minutiae, such as when he breaks down how to use the sine function to determine the size of a U.S. military satellite's telescope mirror based on information gleaned from a photograph the satellite took of an Iranian rocket launch site. Puerile puns peppered throughout don't help (he suggests that manufacturing triangular windows is a "real pane in the glass"). This misses the mark. Agent: PJ Mark, Janklow & Nesbit Assoc. (Aug.)

A thorough explanation of triangles by the popular Australian mathematician, comedian, and bestselling author of Humble Pi. "Triangles are everything," Parker writes in the introduction, "and everything is triangles." The following 10 chapters bear titles like "Going the Distance," "Getting Triggy With It," and "Making Waves." Within his exploratory and everyday applications of triangles, the author describes rounding corners on a racetrack ("the bike did lean just over 45° from vertical. Which means I can officially name my new motorbike gang Hell's Angles"), playing pool ("it's hard to find a more common or more practical use of angles and geometry"), and looking at rainbows, which, he explains, are not arches but circles. Parker delineates myriad laws and patterns, and history as well as recent news. One example of the latter is the March 2023 discovery of the first aperiodic monotile, dubbed "the Hat." "Given this shape had been eluding the entire mathematics community for over half a century," Parker writes, "nobody expected it to be so straightforward." The author has a gift for making somewhat tedious topics not only comprehensible and absorbing, but also great fun. As one example, he refers to Pythagoras ("the granddaddy of triangle maths") as "the Beyoncé of maths" because "who cares about his last name." Parker's tireless enthusiasm, light touch, and inviting manner make for a reading experience akin to a visit to Epcot Center, led by a guide in possession of childlike wonder in addition to adult acumen and humor. The author never gets mired in the weeds, even as he manages to cover a tremendous amount of detailed information, aided by illustrations that feature appealing captions running the gamut from simple to complex. A rare book about math sure to make you smile, despite your feelings about the subject. Once again, Parker measures up. Copyright (c) Kirkus Reviews, used with permission.