He closed the GDZ and pulled a fresh sheet of paper toward him. He didn't copy the answer. Instead, he retraced the steps himself, his pen moving with new confidence. The "Didactic Materials" were no longer a wall; they were a staircase.

—it was the why . He saw the sign-change he’d missed, a tiny error that had derailed his entire solution. The manual showed the elegant transition from a complex fraction to a simple set of coordinates.

Alex stared at a logarithmic inequality that seemed to be written in an alien tongue. His notes from Mr. Petrov’s lecture were a messy blur of coffee stains and half-finished tangents. He was stuck. He wasn't looking for a shortcut to be lazy; he was looking for a lighthouse in a storm.