Can you figure out the connection between the cover image and cubic polynomials?
We open with the third of four installments of our interview with the Theresa Mall Mullarkey Associate Professor of Mathematics at Wellesley College, Karen Lange. In this installment, Prof. Lange describes more technical aspects of her field of expertise: the theory of computation. The Halting Problem and diagonalization arguments feature prominently!
Emily and Jasmine’s long romp through rational rompers, which began with an intriguing social media post, reaches a climax as they succeed in proving one of their main conjecture about them. Specifically, they showed the following: Suppose you have two sequences of whole numbers 
Next, undergraduate Jillian Cervantes and Prof. Pamela E. Harris, both at the University of Wisconsin at Milwaukee, introduce domination sets in graph theory. This is a highly accessible topic and can quickly get you doing mathematics.
Robert Donley introduces standard tableaux in his latest installment of his ongoing series on Shortcuts to Counting.
In a similar spirit to the previous two issue’s Follow Your Nose, we asked Lightning Factorial to try to find the cubic formula without looking it up. We’re not concerned about whether Lightning succeeds or not. What we expect is that by searching for the formula, Lightning will come up with more math along the way. We’ll see!
In Meditate to the Math, we present an opportunity for you to think yourself to understanding and/or proving Descartes’ Rule of Signs.
We conclude with Notes from the Club.
We hope you enjoy it!
Finally, a reminder: when you subscribe to the Girls’ Angle Bulletin, you’re not just getting a subscription to a magazine. You are also gaining access to the Girls’ Angle mentors. We urge all subscribers and members to write us with your math questions or anything else in the Bulletin or having to do with mathematics in general. We will respond. We want you to get active and do mathematics. Parts of the Bulletin are written to induce you to wonder and respond with more questions. Don’t let those questions fade away and become forgotten. Send them to us!
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