English Medium 2021 By S Rajan M Sc M Phil M Ed — 12th Mathematics Chapter Study Material

Arjun smiled and held up the thin, worn-out, white-covered book. “No institute. Just a bridge builder named S. Rajan, M.Sc., M.Phil., M.Ed.”

It wasn't flashy. It had no “50 Sample Papers” or “Crash Course” stickers. Arjan almost put it back, but the price was just thirty rupees. He shrugged and bought it, more out of pity for the old bookseller than hope.

“Dear Student, By now, you have crossed the bridge. Tomorrow, the examiner will not ask you to run faster than anyone else. They will simply ask you to walk steadily. Stay calm. Read the question twice. Show your steps. And remember: a mistake is just a data point, not a verdict. With respect, S. Rajan”

Arjun stared at the mountain of textbooks on his desk. The clock on his wall read 11:47 PM. Outside his window in Patna, the December fog was rolling in, but inside his room, the air was thick with a different kind of pressure. It was 2021, and the CBSE Class 12 Mathematics exam was exactly nine weeks away. Arjun smiled and held up the thin, worn-out,

Week 6: Differential Equations. The study material introduced a simple “Order, Degree, and Method” checklist. It was like a doctor’s diagnostic chart: “Is it variable separable? If yes, do this. Is it linear? If yes, find the Integrating Factor.” No confusion. No panic.

He closed his eyes, saw the clean, white page of the study material in his mind, and wrote the solution. Step by step. Neatly.

His friends asked, “Which coaching institute did you join?” Rajan, M

Two months later, the results came. Arjun scored 95 in Mathematics—his highest mark ever.

That Saturday, his father took him to the old book market near the Gandhi Maidan. Among the piles of dusty, second-hand guides, a thin, unassuming book caught his eye. Its cover was clean, white, and printed in a simple, bold font:

Arjun slept at 10 PM.

It was simple. Human. Logical.

Week 1: Calculus – Continuity and Differentiability. Rajan sir’s material broke the dreaded chain rule into a cooking recipe. “First, peel the outer function (the onion skin). Then, chop the inner function (the vegetable). Cook them together.” For the first time, derivatives made sense.

The night before the exam, Arjun didn't cram. He re-read the final page of S. Rajan’s material. It wasn't a revision formula. It was another letter. He shrugged and bought it, more out of

He slumped over, defeated. "I don't need more problems," he whispered to himself. "I need a key ."

That night, he opened it.