She tracked down John Bellamy’s office number and called. An older, kind voice answered. “Ah,” he said after she explained. “You found my little trap. I plant those solution manuals for the desperate. But here’s the secret: the real solution manual is working through each problem until you understand it well enough to spot my intentional error on page 73.”

But guilt gnawed at her. One night, she noticed a small detail in the solution manual: a tiny handwritten note in the margin beside a root-finding problem. It read: “This was the only problem John got wrong in the first edition. Fix in 2nd printing.”

One evening, in the bowels of the engineering library, Mira whispered a quiet prayer to the gods of Nyquist and Shannon. “If only I had the solution manual,” she muttered.

“You’ve learned more tonight than any solution manual could teach you,” Bellamy said. “Now throw it away. Redo the problems. And when you’re done, mail me your own solutions. I’ll grade them myself.”